Police in Baton Rouge say they have arrested three people who stole guns with the goal of killing police officers. They are still looking for a fourth suspect in the alleged plot, NPR's Greg Allen reports.

"Police say the thefts were at a Baton Rouge pawn shop early Saturday morning," Greg says. "One person was arrested at the scene. Since then, two others have been arrested and six of the eight stolen handguns have been recovered. Police are still looking for one other man."

A 13-year-old boy is among those arrested, Greg says.

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After an international tribunal invalidated Beijing's claims to the South China Sea, Chinese authorities have declared in no uncertain terms that they will be ignoring the ruling.

The Philippines brought the case to the Permanent Court of Arbitration in The Hague, objecting to China's claims to maritime rights in the disputed waters. The tribunal agreed that China had no legal authority to claim the waters, and was infringing on the sovereign rights of the Philippines.

Donald Trump is firing back at Supreme Court Justice Ruth Bader Ginsburg after she made disparaging comments about him in several media interviews. He tweeted late Tuesday that she "has embarrassed all" with her "very dumb" comments about the candidate. Trump ended his tweet with "Her mind is shot - resign!":

Donald Trump wrapped up his public tryout of potential vice presidential candidates in Indiana Tuesday night with Gov. Mike Pence giving the final audition.

The Indiana governor's stock as Trump's possible running mate is believed to be on the rise, with New Jersey Gov. Chris Christie and former House Speaker Newt Gingrich also atop the list. Sources tell NPR the presumptive GOP presidential nominee is close to making a decision, which he's widely expected to announce by Friday.

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The unassuming hero of Jonas Karlsson's clever, Kafkaesque parable is the opposite of a malcontent. Despite scant education, a limited social life, and no prospects for success as it is usually defined, he's that rarity, a most happy fella with an amazing ability to content himself with very little. But one day, returning to his barebones flat from his dead-end, part-time job at a video store, he finds an astronomical bill from an entity called W.R.D. He assumes it's a scam. Actually, it is more sinister-- and it forces him to take a good hard look at his life and values.

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Donald Trump picked a military town — Virginia Beach, Va. — to give a speech Monday on how he would go about overhauling the Department of Veterans Affairs if elected.

He blamed the Obama administration for a string of scandals at the VA during the past two years, and claimed that his rival, Hillary Clinton, has downplayed the problems and won't fix them.

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Deconstructing Dengue: How Old Is That Mosquito?

Feb 11, 2012
Originally published on February 11, 2012 11:46 am

Scientists can spend years working on problems that at first may seem esoteric and rather pointless. For example, there's a scientist in Arizona who's trying to find a way to measure the age of wild mosquitoes.

As weird as that sounds, the work is important for what it will tell scientists about the natural history of mosquitoes. It also could have major implications for human health.

Here's why. There's a nasty disease called dengue that is just beginning to show up in the United States. It's caused by a virus, and it's transmitted from person to person by a mosquito. A mild case of dengue is no worse than flu. A serious case can mean death.

Michael Riehle at the University of Arizona is trying to solve a curious puzzle about dengue: why there have been dozens of cases in nearby Texas and none, or virtually none, in Arizona. Riehle thinks the answer has to do with Arizona's geography.

"It's right on the edge of the range where these dengue mosquitoes are found," he says. "It's a fairly harsh environment, and we think that they might not be surviving long enough to efficiently transfer the disease to other people."

So to test his hypothesis, Riehle wants to be able to compare the life spans of mosquitoes in Arizona with those in Texas.

It's not easy to tell how old a mosquito is: It's not as if they carry around birth certificates or government-issued IDs. Right now the tools for measuring the age of mosquitoes are pretty crude. For example, you can look at a female mosquito's ovaries to see if they have produced any eggs. Riehle says if they have, that means the mosquito is at least five days old, since they can't produce eggs before that. "But that's all it can tell us — less than five days, or more than five days," Riehle says.

So Riehle has a new idea. He wants to see if he can use a mosquito's gene to tell its age.

Looking For Clues In Genes

There are ways to tell when a particular gene is switched on or off in a mosquito. Riehle is looking for genes that switch on or off when the mosquito reaches a particular age. He's found one so far. He needs more in order to make more age estimates.

To help in his search, he raises mosquitoes in a special climate-controlled room down the hall from his office. The insectary is about the size of a large closet with metal shelves floor to ceiling. This place is a Tupperware salesman's dream — the shelves are stuffed with plastic containers in a variety of convenient sizes. It's a level 2 containment facility, so the mosquitoes won't get out.

Since he knows exactly when mosquitoes are born in the lab, that gives him a precise starting point to see how, or if, different genes change over time. If he can find genes that change with age in the lab, Riehle can look for the same genes in wild mosquitoes and use them to estimate the wild mosquitoes' age.

This work has implications for a number of mosquito-borne diseases. Malaria mosquitoes need to live at least two weeks before they can transmit the malaria parasite. Knowing more about the age of wild mosquito populations could help prevent, or at least predict, outbreaks of disease.

But the search for age-related genes is going slowly.

That's not terribly surprising. In science, you usually have to go down a lot of blind alleys before you find what you're looking for, if you ever do. Riehle says it's a lesson students coming into his lab have to learn.

"You give them a project, and they just expect it to work, have no problems, get their results by the end of the semester, and they're on their way," he says. "It's always interesting to see them learn that, yeah, a lot of science is failure and building upon what doesn't work."

Failure is inevitable in science, so it's not failure itself that's bad, it's just not learning anything from your failures. "Actually, what we call failure a lot of times leads to new lines of discovery," says Riehle.

So Riehle will continue to search for genes that will reveal a mosquito's age. With persistence, and enough failures, he thinks he'll find them.

Copyright 2014 NPR. To see more, visit http://www.npr.org/.

Transcript

SCOTT SIMON, HOST:

You know, scientists can spend years working on problems that at first may seem to many people kind of pointless. For example, there's a researcher in Arizona who's trying to find a way to measure the age of - ooh, sorry. mosquitoes.

But as NPR's Joe Palca reports, if it's successful, the work will not only be professionally rewarding, it could have major implications for human health.

JOE PALCA, BYLINE: There's a nasty disease called dengue that's just beginning to show up in the United States. It's caused by a virus, and it's transmitted from person to person by a mosquito. A mild case of dengue is no worse than flu. A serious case can mean death.

Michael Riehle is at the University of Arizona in Tucson. He's trying to solve a curious puzzle about dengue - why there have been dozens of cases in nearby Texas and none - or virtually none - in Arizona. Riehle thinks the answer has to do with Arizona's geography.

MICHAEL RIEHLE: It's right on the edge of the range where these dengue mosquitoes are found. It's a fairly harsh environment, and we think that they might not be surviving long enough to efficiently transfer the disease to other people.

PALCA: So to test his hypothesis, Riehle wants to be able to compare the life spans of mosquitoes in Arizona with those in Texas. It's not easy to tell how old a mosquito is. It's not as if they carry around birth certificates or government-issued IDs.

Right now the tools for measuring the age of a mosquito are pretty crude. For example, you can look at a female mosquito's ovaries to see if they've produced any eggs. Riehle says if they have, that means the mosquito is at least five days old, since they can't produce eggs before that.

RIEHLE: But that's all it can tell us, less than 5 days or more than 5 days.

PALCA: So Riehle has a new idea. He wants to see if he can use a mosquito's genes to tell its age. There are ways to tell when a particular gene is switched on or off in a mosquito. Riehle is looking for genes that switch on or off when the mosquito reaches a particular age. He's found one. He needs more in order to make more accurate predictions. To help in his search, Riehle raises mosquitoes in a special climate-controlled room down the hall from his office.

RIEHLE: So this is the basic insectory. This is a level 2 containment facility so the mosquitoes won't get out.

PALCA: The insectory is about the size of a large closet with metal shelves floor to ceiling. This place is a Tupperware salesman's dream. The shelves are stuffed with plastic containers in a variety of convenient sizes. Riehle points to a large-ish container. Inside are what look like tiny wiggling worms swimming around in a couple inches of water.

RIEHLE: There's a whole bunch of pupae in there that you can see. These will all come out in the cage and then after two days of allowing them to hatch in there we'll know the exact age of the mosquito.

PALCA: Knowing its age gives him a precise starting point to see how or if different genes change over time. If he can find genes that change with age in the lab, Riehle can look for the same genes in wild mosquitoes and use them to estimate the wild mosquito's age.

This work has implications for a number of mosquito-borne diseases. Malaria mosquitoes have to live at least two weeks or so before they can transmit the malaria parasite. Knowing more about the age of wild mosquito populations could help prevent, or at least predict, outbreaks of disease.

But the search for age-related genes is going slowly. That's not terribly surprising. In science, you usually have to go down a lot of blind allies before you find what you're looking for, if you ever do. Riehle says it's a lesson students coming into to his lab have to learn.

RIEHLE: You give them a project and they just expect it to work and have no problems and get their results by the end of the semester and they're on their way. And it's always interesting to see them learn that, yeah, a lot of science is failure and building upon what doesn't work.

PALCA: So it's not failure itself that's bad, it's just not learning anything from your failures.

RIEHLE: Exactly. Yeah. Actually, what we call failure a lot of times leads to new lines of discovery.

PALCA: So Riehle will continue to search for genes that will reveal a mosquito's age. And with persistence, and enough failures, he thinks he'll find them.

Joe Palca, NPR News. Transcript provided by NPR, Copyright NPR.