Swarm-mongering: Brainless blobs flock together

Birds of a feather flock together and now so do brainless, inanimate blobs. Made of microscopic particles, the artificial swarms could shed light on the mysterious mechanisms behind the natural swarming seen in fish and birds. They might also lead to materials with novel properties like self-healing.

Animals such as birds, fish and even humans that move together in swarms have individual intelligence, but Jérémie Palacci of New York University and colleagues wondered whether inanimate objects could also swarm. "From a physicist's point of view, if many different systems behave in the same way there must be an underlying physical rule," he says.

To explore this idea, the team created microscopic plastic spheres, each one with a cubic patch of haematite, an iron oxide, on its surface. When submerged in hydrogen peroxide, the spheres spread out in a disordered fashion. The team then shone blue light on the particles, causing the haematite cubes to catalyse the breakdown of any nearby hydrogen peroxide into water and oxygen. As hydrogen peroxide concentration dropped temporarily in these regions due to the reaction, osmotic forces cause more hydrogen peroxide to flow into them, and that in turn buffets the spheres. The whole process then repeats.

Self-healing swarm

When two spheres come close enough to each other, the balance of chemical forces shifts so that the two spheres are attracted. If there are enough spheres in the same place they will cluster together to form shapes of symmetrically arranged particles, which the team call crystals (see video, above). These crystals continue to be buffeted by the movement caused by the breakdown of hydrogen peroxide – but now they move together as one object, replicating a life-like swarm. Switch off the light, however, and the reaction stops, causing the crystal to lose the forces that hold it together, and the particle distribution becomes disordered once again.

"This system shows that even though the particles have no social interaction or intelligence, you can exhibit collective behaviour with no biology involved," says Palacci. Since the haematite is magnetic, it is even possible to steer the crystals in one direction by applying a magnetic field. Such control might be useful if the artificial swarms are to be harnessed for applications.

As the particles automatically fill any gaps that form in the crystal, again thanks to the chemical dynamics of the system, they could be used to create a self-assembling, self-healing material. The work is published in the journal Science today.

Schooled by fish

Iain Couzin of Princeton University says these kinds of systems are very useful for studying biological collective behaviour because researchers have complete control over their interactions – unlike natural systems.

His team has its own swarming experiment published in the same issue of Science, based on schools of fish that prefer to stay in shade. Their paper shows that shining a light on some of the fish in the school causes them to speed up, to get away from the light. But as a result, non-illuminated fish also speed up, even though, if acting purely as individuals, they would have had no reason to do so. "We show just by using simple interactions that schools can have a sense of responsiveness to the environment that individuals do not have," he says.

Couzin sees no reason why such behaviour should be limited to natural systems. "In future it may be possible to create systems of particles that can make collective decisions – something we often think of as only possible in biological systems," he says.

Journal references: Living crystals: Science, DOI: 10.1126/science.1230020; Fish: Science, DOI: 10.1126/science.1225883

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14 dead in Mexico City skyscraper blast: government

MEXICO CITY: At least 14 people died and 80 were injured in a blast that rocked the Mexico City skyscraper that houses the headquarters of oil giant Pemex on Thursday, Mexico's interior minister said.

"We have 13 dead at the scene and one more at the hospital. There are more than 80 wounded and we continue to look for survivors in the debris," Interior Minister Miguel Angel Osorio Chong told reporters.

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14 killed in blast at offices of Mexican state oil company

By CNN Staff

updated 7:55 PM EST, Thu January 31, 2013

STORY HIGHLIGHTS

• NEW: Witness: "People were screaming. ... You could see pieces of the wall falling"


• Fourteen people were killed in the blast, Mexico's interior minister says


• At least 80 people were injured, he says


• Some people are trapped in building's basement, the CNN affiliate says

Mexico City (CNN) -- An explosion rocked the offices of Mexico's state oil company Thursday, killing at least 14 people and injuring dozens more, the country's interior minister said.

At least 80 people were injured in the Mexico City blast, Interior Minister Miguel Angel Osorio Chong told reporters.

Dozens of people were trapped in the building after the blast, Foro TV reported.

Rescuers were searching for survivors in basement of the large office tower, Osorio Chong said.

"People were screaming. ... You could see pieces of the wall falling to the ground," said Joaquin Borrell Valenzuela, an attorney for the Pemex comptroller's office who was in a courtyard outside the building at the time of the blast.

The blast prompted an evacuation of personnel from the Pemex offices, a company spokesman told Notimex.

A large plume of smoke rose near the office tower after the explosion.

Images from the scene showed emergency rescue teams carrying people on stretchers.

Authorities said helicopters carried some of the wounded to hospitals.

It was unclear what caused the explosion, which occurred in the building's basement, Pemex spokesman Francisco Montano told Notimex.

CNN's Rafael Romo, Edwin Mesa, Christine Theodorou, Rey Rodriguez and Rene Hernandez and CNNMexico.com contributed to this report.

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14 dead, 80 injured in Mexico oil company blast

Updated 7:52 PM ET

MEXICO CITY An explosion at the main headquarters of Mexico's state-owned oil company in the capital Thursday killed 14 people and injured 80 as it heavily damaged three floors of the building, sending hundreds into the streets and a large plume of smoke over the skyline.

There were also reports that as many as 30 people were trapped in the debris from the explosion, which occurred in the basement of an administrative building next to the iconic, 52-story tower of Petroleos Mexicanos, or Pemex. There was no immediate cause given for the blast.

"It was an explosion, a shock, the lights went out and suddenly there was a lot of debris," employee Cristian Obele told Milenio television, adding that he had been injured in the leg. "Co-workers helped us get out of the building."

The tower, where several thousand people work, was evacuated. The main floor and the mezzanine of the auxiliary building, where the explosion occurred, were heavily damaged, along with windows as far as three floors up.

"We were talking and all of sudden we heard an explosion with white smoke and glass falling from the windows," said Maria Concepcion Andrade, 42, who lives on the block of Pemex building. "People started running from the building covered in dust. A lot of pieces were flying."

A reporter at the scene saw rescue workers trying to free several workers trapped. Television images showed people being evacuated by office chairs, and gurneys. Most of them had injuries likely caused by falling debris.

Police landed four rescue helicopters to remove the dead or injured. About a dozen tow trucks were furiously moving cars to make more landing room for the helicopters.

In an earlier Tweet, the company said it had evacuated the building as a precautionary measure because of a problem with the electrical system in the complex that includes the skyscraper. It tweeted that several workers were injured.

Streets surrounding the building were closed as evacuees wandered around, and rescue crews loaded the injured into ambulances.

Interior Department spokesman Eduardo Sanchez confirmed that an explosion in a basement garage damaged the first and second floors of the auxiliary building, which is located in a busy commercial and residential area.

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What If Undocumented Immigrants Had Voted?

If every undocumented immigrant had cast a vote for President Obama in 2012, he would have won Arizona, Georgia, North Carolina and Texas, and he would have beaten Mitt Romney by nearly 11 percentage points nationally, instead of three.

Only citizens can vote, however, and 11.2 million unauthorized residents didn't get the chance.

But with immigration overhaul on the table, legalizing new Democratic voters looms as a threat for conservatives who don't want to hand their political foes a potential windfall of 11.2 million new voters with the creation of a pathway to citizenship -- and to voting rights -- with a comprehensive bill.

"The fear that many people have is that the Democrats aren't interested in border security, that they want this influx," Rush Limbaugh griped during his Tuesday interview with overhaul champion Sen. Marco Rubio of Florida. "For example, if 70 percent of the Hispanic vote went Republican, do you think the Democrats would be for any part of this legislation?"

New immigration policies could mean in influx of new voters, but Republicans needn't worry about it in the short term.

See Also: Gang of Eight Accelerates Immigration Reform Pace

"Under almost any scenario, it's pretty far in the distance," Jeff Passell, senior demographer at the Pew Hispanic Center, said of the prospect that unauthorized immigrants' gaining voting rights would pump up numbers significantly enough to meaningfully change the U.S. electorate.

Whitney Curtis/Getty Images

And yet, the "influx" wouldn't be negligible: "Realistically, we're talking about potentially adding probably 5 million potential voters or so in 10 years," he said.

Hispanic voters broke 71 percent for Obama in November, and Republican strategists recognize that the party has failed to court Hispanic voters effectively. But depending on how slowly the citizenship line moves, the Republican Party will have a decade or so to shake its anti-Hispanic stigma.

See also: A Glossary for Immigration Reform

"It's a long time coming. You're talking about 15 to 20 years before we're talking about a whole slew of new voters coming into the electorate," said Jennifer Korn, executive director of the Hispanic Leadership Network, who served as Hispanic outreach director for George W. Bush's presidential campaign.

"If Republicans can map out and change their positions with things that Hispanics do support -- on less government, lower taxes, less regulations on small businesses -- then they can really compete for the Hispanic vote over the next 20, 30 years."

There are 11.2 unauthorized immigrants living in the United States, according to the Pew Hispanic Center's estimate. While most are of voting age (Pew estimates just 1 million younger than 18), the deluge of new Democratic voters might not be as substantial as Limbaugh implied.

In other words, it's not as if Democrats will gain 11.2 million votes in the next few years. Here are some things to keep in mind:

• Not All Hispanics Vote for Democrats. Most do, but not all, and voter preferences vary from state to state. In Florida, 60 percent of Hispanic voters backed Obama, according to 2012 exit polls; in Arizona, 74 percent voted for the president. Even if all 11.2 million had voted in 2012, Obama would only have picked up North Carolina if they simply hewed to Hispanic voter trends. Romney still would have carried Arizona, Georgia and Texas, although he would have won Georgia by less than 1 percentage point. (Note: There were no exit polls in Texas or Georgia, and here the national rate provides rough estimates of how results would have changed.)

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Today on New Scientist: 30 January 2013

Timbuktu's precious scientific texts must be saved

Islamist militants in Mali have burned documents that attest to science in Africa before European colonisation - what remains must be protected

Think that massage feels good? Try adding drugs

Nerve bundles that respond to stroking have been identified and chemically activated in mice

How Obama will deliver his climate promise

The US is set to meet - and maybe exceed - Obama's pledge to cut US emissions by 17 per cent, which could give a boost to international climate talks

Minimum booze price will rein in alcohol abuse

Evidence suggests the UK government's proposal to set a minimum price for alcohol could save thousands of lives, and billions of pounds of public money

First real time-travel movies are loopers

Hollywood has played with time travel for decades, but now physicists have the first movies of what travelling to the past actually looks like

Surfer rides highest wave ever caught

Garret McNamara of Hawaii claims to have ridden the highest wave ever caught by a surfer, a 30-metre monster off the coast of Nazaré, Portugal

Infrared laptop trackpad ignores accidental touches

Longpad is a touchpad that extends the full width of your laptop and uses infrared sensors to ignore any unwanted touches

Close call coming: Averting the asteroid threat

With an errant space rock heading this way, just how good are our asteroid defences - and how do we avert the cataclysm?

The right to fight: women at war

The US military has accepted women into combat. What can science tell us about how women deal with being in the line of fire? And are they any different to men?

Earth and others lose status as Goldilocks worlds

Several planets are taking a hit thanks to a redefinition of the habitable zone - the area around a star in which liquid water can theoretically exist

The 10,000-year bender: Why humans love a tipple

Our taste for alcohol results from an evolutionary tussle between humans and yeast - one in which the microbes have often had the upper hand

Read More..

Japan December factory output up 2.5% on-month

TOKYO: Japan on Thursday said the nation's factory output for December rose 2.5 per cent from the previous month thanks to brisk production of cars and semiconductors.

The gain -- still worse than a 4.0 per cent expansion expected by the market -- came as Japan's new government under Prime Minister Shinzo Abe vows to breathe new life into the world's third-largest economy with huge stimulus and easing aimed at tackling long-running deflation.

"Industrial production shows signs of having bottomed out," said a statement from the economy ministry.

The ministry added that a survey of manufacturers found they expected another output increase for January and February of 2.6 per cent and 2.3 per cent, respectively.

Annual industrial output figures were not immediately released, but on a quarterly basis the country's factory output was down 1.9 per cent from the previous three months.

And the rosy monthly data comes just a week after Japan said it logged a record trade deficit for 2012 as exports were hit by a bitter diplomatic spat with its biggest market China and plunging demand in debt-wracked Europe.

Japan's economy contracted in the third quarter, meeting the technical definition of a recession.

The figures underscored the size of the task ahead for the new government which has heaped pressure on the Bank of Japan for aggressive easing measures to boost the country's fortunes.

- AFP/ck

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Interstate littered with cars after North Georgia tornado

STORY HIGHLIGHTS

• Much of the affected region sees huge temperature extremes


• A Georgia TV news crew sees tornado form; damage is reported in Adairsville


• Nearly 20 are injured in Georgia; several are trapped for a time


• A Tennessee man dies when a tree falls on his home, emergency managers say

Is there severe weather near you? Share your photos and videos on iReport, but stay safe.

(CNN) -- Powerful winds and a tornado spawned by a 1,000-mile-long storm system pounded communities in northwest Georgia on Wednesday, overturning dozens of vehicles and trapping residents.

The tornado caused significant damage in Adairsville, Georgia.

One person died in that town and another died in Tennessee, authorities reported. At least 17 people were injured in Georgia, two critically.

The Adairsville death marks the first person killed by a U.S. tornado in 220 days, a record for most consecutive days without such a fatality, said CNN meteorologist Dave Hennen.

Severe weather 101

The storm churned eastward, prompting severe thunderstorm and flash-flood warnings in eastern Tennessee and western portions of the Carolinas. The front has led to nearly 400 reports of severe wind and 20 of tornadoes over two days, from Texas to Pennsylvania.

In the Adairsville storm, winds caused significant damage to a motel and a manufacturing plant, according to Craig Millsap, fire chief and interim emergency management director for Bartow County. The motel's guests are believed safe and workers at the Daiki plant have all been accounted for, he said.

Daiki employees hid in a kitchen and bathroom as the tornado snatched the roof off and left much of the plant in ruin. Two workers suffered minor injuries.

The driver of a commercial truck that was overturned near Adairsville said the storm "grew legs and just started accelerating." He told CNN Atlanta affiliate WGCL he was unscathed. "There is no way in the world that if you see this debris behind me I should be alive."

The National Weather Service reported major structural damage and overturned cars in downtown Adairsville, where a news crew for CNN affiliate WSB-TV witnessed a tornado form and touch down Wednesday morning.

The death came when a building collapsed, Millsap said.

10 deadliest U.S. tornadoes

Nine people in Bartow County suffered non-life-threatening injuries, according to the Georgia Emergency Management Agency.

The storm caused major damage on and near Interstate 75, the Georgia Department of Transportation said. The weather service, citing emergency management officials, said dozens of cars had been overturned near Exit 306 at Adairsville.

Officials reported up to 100 homes damaged in Bartow and Gordon counties. Georgia emergency officials reported eight injuries in Gordon County, north of Adairsville. Two of the injuries were described as critical.

Interactive: Check your forecast

"There have been a number of entrapments and deputies, firemen and emergency personnel have all been working to free those people," said Gordon County Chief Deputy Sheriff Robert Paris. "I don't believe we have any more trapped at this time."

The tornado struck a subdivision that also was hit by storms in 2011, Paris said. "This one appears to be much, much worse. But this was almost the same path. There were some people that had to go through both of them."

Gov. Nathan Deal declared a state of emergency for both counties. State officials late Wednesday afternoon said they had no reports of anyone unaccounted for, but searches of homes and businesses were continuing.

Trees and power lines were down as the result of a possible tornado in Georgia's Gilmer County, the weather service said.

KFVS: Power outages from storm

Utilities reported about 21,000 customers without power in west and north Georgia and metropolitan Atlanta.

In Tennessee, a 47-year-old man died early Wednesday when high winds toppled a tree onto a roof in Nashville, the Tennessee Emergency Management Agency said. CNN affiliate WSMV said the victim was in a building next to a home.

Other injuries were reported in Chester, McNairy and Henderson counties, emergency management spokesman Jeremy Heidt said.

The National Weather Service also reported severe weather or damage Wednesday in Texas, Mississippi and Alabama. Tornadoes were confirmed in Marion County, Kentucky, and Harrison County, Indiana.

WBKO: Tractor trailer flips on I-65

Northern Florida, eastern Georgia, much of South Carolina and portions of North Carolina, Virginia and Maryland were under a tornado watch Wednesday evening.

CNN meteorologist Chad Myers said the massive storm system was 1,000 miles north to south, moving east in a belt that will eventually stretch from New York to Florida.

"If it's hot and humid where you are, then you are still in the danger zone," Myers said. "Storms can still be coming to you tonight. ... The cold air is on the back side of it."

The strong cold front causing the severe weather brought huge extremes in temperature readings. Thermometers reached the low 80s in parts of southeast Georgia and South Carolina, the 50s in Tennessee and the 30s in Illinois.

WFIE: Storms blow new roof off tri-state church

Earlier, in Alabama, the storms blew the metal roof off a building in Sheffield, CNN affiliate WHNT said. The storm also damaged a church steeple in Rogersville, the station reported.

In Kentucky, winds blew off much of the roof of the Penrod Missionary Baptist Church and damaged several homes, CNN affiliate WFIE reported.

In Nashville, the weather service listed dozens of damage reports across the region: a funnel cloud was reported early Wednesday in Jackson County, there were dozens of reports of downed trees and power lines, and law enforcement reported damage to homes and businesses.

CNN affiliate WSMV also reported the partial collapse of an office building in Mount Juliet.

"I built it myself to take an event like this. And it looks like a freight train hit it," the station quoted building owner Dewey Lineberry as saying. "It's just destroyed. It laid the building down on top of cars, it put the building on top of people. It's unbelievable."

Workers who were inside the building when the storm hit took cover under mattresses, the station said.

The storm came dangerously close to WSMV, the station reported: Workers had to move to a safe room when a buzzer in the newsroom alerted them of storm danger around 4 a.m. Wednesday, the station reported.

WKRN: Confirmed tornado

CNN iReporter Matt Davis said overnight storms damaged a historic brick structure on Fairvue Plantation in Gallatin, Tennessee.

"The plantation was a horse farm. Those (structures) have been standing there for 100 to 200 years. It was sad to see those collapsed and caved in. It's historic to the neighborhood," the high school student said.

On Tuesday, the storms raked Arkansas, Louisiana and Mississippi, among other places, with heavy rain and high wind.

Photos: Finding art in icy weather

CNN's Ben Brumfield, Ryan Rios and Miguel Marquez contributed to this report.

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Storm system moves into Ga., blamed for 2 deaths

Updated 6:45 p.m. ET

ADAIRSVILLE, Ga. A massive storm system raked the Southeast on Wednesday, spawning tornadoes and dangerous winds that overturned cars on a Georgia interstate and demolished homes and businesses, killing at least two people.

The storm system tossed vehicles on Interstate 75 in Georgia into the air, onto their roofs and into the grassy shoulder. The highway was closed for a time, and another main thoroughfare remained closed until crews could safely remove downed trees and power lines from the road. Authorities were working to rescue people reportedly trapped in homes and buildings.

The storm decimated that city's downtown area and wiped out parts of a large manufacturing plant, killing at least one person and sending nine to hospitals, Bartow County officials said. Residents said no traces remained of some roadside produce stands — a common sight on rural Georgia's back roads.

A funnel cloud in northern Georgia on Jan. 30, 2013

/

WGCL-TV

Georgia Governor Nathan Deal declared a state of emergency for Bartow and Gordon counties. Georgia Power reports there are 10,200 outages statewide. Of the 10,200, 5,600 outages are in the Adairsville Area and 3,500 in metro Atlanta, reports CBS affiliate WGCL-TV in Atlanta.

One other death was reported in Tennessee after an uprooted tree fell onto a storage shed where a man had taken shelter.

In Adairsville, the strange mix of debris in one yard showed just how dangerous the storm had been: a bathtub, table, rolls of toilet paper and lumber lay in the grass next to what appears to be a roof. Sheets of metal dangled from a large tree like ornaments.

"The sky was swirling," said Theresa Chitwood, who owns the Adairsville Travel Plaza. She said she went outside to move her car because she thought it was going to hail. Instead, the passing storm decimated a building behind the travel plaza and ripped the roof off of a nearby bank.

"It sounded like a freight train coming through," she said. "It looks like a bomb hit it."

Juanita Carter told CBS News she was sleeping when the tornado hit; a dangerous situation. "I was hanging. My back was across those blocks," she said. "I don't remember nothing after that. I blacked out."

17 Photos

Massive storm system hits the South

Powerful winds ripped through the entire region, with gusts powerful enough to topple tractor-trailers in several places.

Conditions remained ripe for tornadoes into Wednesday afternoon, and authorities were still investigating several sites to determine if damage was caused by twisters. Since Tuesday, the system had caused damage across a swath from Missouri to Georgia.

In recent days, people in the South and Midwest had enjoyed unseasonably balmy temperatures in the 60s and 70s. A system pulling warm weather from the Gulf of Mexico was colliding with a cold front moving in from the west, creating volatility.

One person was reported injured by lightning in Arkansas during the storm's eastward trek. Two people suffered minor injuries when a mobile home was blown off its foundation in Kentucky. Only one minor injury was reported in Mississippi, where officials praised residents for heeding warnings and being prepared.

In Tennessee, officials confirmed that a tornado with peak wind speeds of 115 mph touched down in Mount Juliet. No serious injuries were reported there, though the path of damage was about 150 yards wide, including homes, a warehouse and an automotive business.

At a shopping center in Mount Juliet, large sheets of metal littered the parking lot, light poles were knocked down and bits of fiberglass insulation were stuck in the trees.

One wall of a Dollar General convenience store collapsed, and the roof was torn off. Mark Fulks Jr. runs Mark's Automotive with his father in a building attached to the Dollar General. The garage door was blown off his shop and sitting on one of the cars inside, and Fulks said several of the cars they were working on had their windshields blown out.

A nearby office building and a distribution center for The Tennessean newspaper also had severe damage. Rick Martin, who bags the newspapers and helps his wife deliver them, was shocked when he saw what was left of the distribution center.

The metal frame of the building still stood, but its cinderblock walls had crumbled, and papers and plastic bags littered the trees.

"We feel real lucky," he said on Wednesday morning as looked at the damage. "I would have hated to be in here when this happened."

The nation has had its longest break between tornado fatalities since detailed tornado records began being kept in 1950, according to the Storm Prediction Center and National Climatic Data Center. The last one was June 24, when a person was killed in a home in Highlands County, Fla. That was 220 days ago as of Tuesday.

The last day with multiple fatalities was June 4, when three people were killed in a mobile home in Scott County, Mo.

CBS meteorologist David Bernard reports there were tornado watches stretching from Tallahassee, Fla., through Georgia and the Carolinas Wednesday night. The Washington, D.C., area was also under a tornado watch.

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Obama Confident Immigration Reform Will Pass

President Barack Obama expressed confidence on Wednesday that he would sign comprehensive immigration reform into law by the end of this year.

In an interview with Univision's Maria Elena Salinas, Obama explained that significant details of a bill still must be worked out by lawmakers, including the structure of a pathway to citizenship for many of the 11 million undocumented immigrants. But Obama said that the progress made by a bipartisan group of lawmakers in the Senate has given him hope that a deal can get done.

See Also: What Will Be Obama's Immigration Legacy?

When asked by Salinas if we will have immigration reform by the end of the year, Obama said, "I believe so."

"You can tell our audience, 'Sí, se puede?'" Salinas asked.

"Sí, se puede," Obama responded.

Later in the interview, Obama said that he hopes a bill could be passed as early as this summer.

But cognizant of deep divisions a topic like immigration has sewn in the past, Obama said that's contingent on bipartisan negotiations continuing to proceed well.

"The only way this is going to get done is if the Republicans continue to work with Democrats in Congress, in both chambers, to get a bill to my desk," he said. "And I'm going to keep on pushing as hard as I can. I believe that the mood is right."

Although the president threatened to introduce his own bill if negotiations in Congress stall during his speech in Las Vegas, Nevada, on Tuesday, he said he is content to let lawmakers hash out the details among themselves for the time being.

"If they are on a path as they have already said, where they want to get a bill done by March, then I think that's a reasonable timeline and I think we can get that done. I'm not going to lay down a particular date because I want to give them a little room to debate," he said. "If it slips a week, that's one thing. If it starts slipping three months, that's a problem."

The president's principles and the Senate's principles on immigration broadly align with one another, but there are still thorny issues that could spark a division between Obama and Republicans, such as the pathway to citizenship.

The Senate's path to citizenship would allow many undocumented immigrants to obtain legal status immediately upon passage of the law. But their ability to then seek legal permanent residency would be contingent upon the U.S.-Mexico border being deemed secure. Sen. Marco Rubio (R-Fla.), a member of the bipartisan "Gang of Eight" on immigration, has been particularly vocal in stating that border security is a precondition for gaining legal permanent residence, and then citizenship.

While the White House has said that it is withholding judgment on that plan until actual legislative language is drafted, Obama said that he wants a bill that makes it clear from the outset that undocumented immigrants eligible to earn their way to citizenship can eventually obtain it.

"What we don't want to do is create some kind of vague prospect in the future that somehow comprehensive immigration reform that includes a pathway to citizenship will happen, you know, mañana," Obama said. "We want to make sure we are very clear this legislation provides a real pathway."

The president said that enhancing border security measures and workplace enforcement provisions are a part of his plan, as well as the Senate's, and cited his administration's efforts to bulk up border security during the past four years, saying that illegal crossings have dropped 80 percent since 2000.

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