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Trump Has It Backward: Many Migrants Are Victims of Crime

NY Times - Tue, 2018-09-18 09:45
Ramped-up enforcement by the United States and Mexico has pushed migrants onto more invisible, risky paths and put them at greater danger.

Environmental DNA sniffs out sharks

Futurity.org - Tue, 2018-09-18 09:39

A white shark’s acute sense of smell allows it to detect a potential meal several miles away. Now, using environmental DNA (eDNA), scientists—and someday, perhaps, any curious person—can sniff them out as well, according to new research.

“One of the goals of this research is for a lifeguard to be able to walk down to the shore, scoop up some water, shake it, and see if white sharks are around,” says Kevin Lafferty, an ecologist with the US Geological Survey and a researcher with the Marine Science Institute at the University of California, Santa Barbara. Lafferty is lead author of the paper, which appears in Frontiers in Marine Science.

The team’s results add to a growing body of evidence that white sharks, which had been declining in numbers due to overfishing, have for the last several years been experiencing a comeback along the California coast.

Stuff in the water

The resurgence is due to the success of state and federal protections from fishing, recovery of marine mammal populations, and better fisheries management, says coauthor Chris Lowe, a professor at California State University, Long Beach.

“However, white shark population recovery has co-occurred during a period when more people than ever before are using the coastal ocean for recreation, ultimately increasing the likelihood of interactions,” he says.

“While sightings of juvenile white sharks have risen considerably along California over the last eight years, there has been no dramatic increase in shark bites on people.”

Environmental DNA is genetic material collected from the environment, as opposed to within a living organism. Things animals may leave behind—such as mucus, feces, or shed skin—contain their genetic signatures, which researchers can parse out and identify through genetic sequencing.

Scientists can extract and amplify specific genes within the DNA fragments found in water samples, and determine if the DNA contained in those samples is from a specific species.

Better testing

In Carpinteria, down the coast from UC Santa Barbara, Lowe had been acoustic- and satellite-tracking tagged juvenile sharks at one of several summer/fall nurseries along southern California.

Lafferty and Lowe wondered if the sharks were leaving a detectable eDNA plume. Lafferty had little success using eDNA to sample for sharks until eDNA expert and MSI researcher Chris Jerde shared a new protocol he developed with Andrew Mahon, a biology professor at Central Michigan University and study coauthor.

“Ten years ago we started working on eDNA,” says Jerde, who is a coauthor of the paper. “The advances in technology since then have dramatically improved the reliability, portability, and widespread application of the method.”

Mistaken identity

Using a new species-specific genetic analysis called digital droplet PCR, Mahon designed specific genetic markers from white shark tissue Lowe sent to him. Mahon’s student, Kasey Benesh, analyzed the water samples and controls blindly. Samples near the shark aggregation matched the genes in the white shark tissue, whereas water samples a mile away did not, confirming that a water sample could sniff out white sharks.

Because eDNA can drift with currents, and sharks can swim long distances in the time it takes eDNA to degrade, the new approach only gives a rough idea about where sharks actually are at a particular moment. Still, “Chris Lowe can now add eDNA to his new white shark monitoring program, which includes real-time acoustic tracking and drone flights,” Lafferty says.

For surfers, ocean swimmers, and beachgoers, the increase in white shark population may be a cause for concern. Although white sharks don’t feed on humans (and juveniles favor rays and other fish), they have certainly been known to bite out of defensiveness, curiosity, or mistaken identity, causing grave or lethal injuries.

Shark alert texts

Environmental DNA monitoring could give lifeguards and other people responsible for public safety clues as to when to be extra vigilant, and also help marine biologists understand how well white sharks are recovering in response to protection.

“We can now sample eDNA along the coast to make better maps and seasons for white sharks,” Lafferty said, “And if we can do it for white sharks, we can do it for other marine species, too.”

“We can use eDNA not only to determine whether white sharks have been present at a beach, but also to determine if their favorite food is there is well, such as stingrays,” Lowe says.

“Once we are able to better refine and calibrate the methods, another goal will be to integrate eDNA technology into autonomous surface vehicles that can be programmed to move along the coast sampling water and send data into the cloud, along with text alerts to local lifeguards, of the presence of white sharks at a particular location. This technology holds great promise for future, near real-time monitoring.”

The findings show that eDNA sequencing has become a powerful tool for tracking the general movement of single species, as well as for monitoring the biodiversity of a region in real time, the researchers say.

Initially a tool to detect the presence of invasive species, such as Asian carp and bullfrogs, researchers have also used eDNA to detect threatened and endangered species that are often elusive, such as arroyo toads, California red-legged frogs, and tidewater gobies.

“New advances in eDNA are allowing for not just a single species to be detected, but instead the DNA for the water sample is screened for all fish species or all amphibian species,” Jerde says.

“The same technology used to decode the human genome is now used to sequence all the DNA in a water sample. From this we can monitor fish stocks, measure the presence or absence of rare species, and better connect how climate change and pollution are impacting biodiversity.”

UCSB’s Marine Biodiversity Observation Network supported the study.

Source: UC Santa Barbara

The post Environmental DNA sniffs out sharks appeared first on Futurity.

Library loans more than books to job-hunters

CNN - Tue, 2018-09-18 09:36
For a young person, going to a job interview can be expensive. You need nice clothes and a case or handbag to hold your resume and other documents.

Amazon's latest Prime-exclusive discount is the Fire TV 4K for just $40

CrackBerry - Tue, 2018-09-18 09:32

Amazon's back with another deal for Prime members, this time it has dropped the Fire TV 4K down to a great price!

It pays to be a Prime member.

Update: If you're concerned about streaming due to a slow or weak Wi-Fi connection at home, this discounted Amazon Ethernet Adapter for Fire TV devices can help you achieve a stronger connection for just $12 right now.

Amazon has been dishing out discounts on its own hardware to Prime members for about a week now, and the latest device to receive the treatment is the Fire TV 4K. Right now, Prime members can pick one up for just $39.99, which is the same price as what we recently saw the refurbished version go on sale for. This is one of the best prices we've seen on this hardware, outside of Prime Day where it was just a few bucks less.

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Trump Hits China With Tariffs on $200 Billion in Goods, Escalating Trade War

NY Times - Tue, 2018-09-18 09:29
The president said the tariffs, which will hit everyday consumer products, will go into effect on Sept. 24.

White House slashes refugee cap to new low

CNN - Tue, 2018-09-18 09:27
The Trump administration will cap refugee admissions at the lowest levels since the refugee resettlement program began, Secretary of State Mike Pompeo announced. It's the second year in a row the administration has set the cap at a record low.

Why a 'Black-ish' star wore Nike

CNN - Tue, 2018-09-18 09:25
"Black-ish" actress Jenifer Lewis wore a red and black Nike shirt on the Emmys red carpet Monday night as a message of support for the company's decision to promote Colin Kaepernick.

Introducing Classic View, a new way for subscribers to browse Ars

Ars - Tue, 2018-09-18 09:15

Enlarge (credit: Aurich / Getty)

We launched Ars Pro, our ad-free subscription service, at the beginning of the year. At the time, we told you we wanted to hear your ideas on how to make Ars Pro and Ars Pro++ more compelling. And we've been listening. Last spring, we removed tracking scripts for subscribers. More recently, we added PayPal as a payment option in response to your feedback. Today, we're excited to offer Classic View, an old-school way of browsing the front page.

When Ars launched in 1998—two whole decades ago—it was a simple site with the entire text of stories appearing on the front page. The only exceptions were things like Cæsar's lengthy musings on the blue-and-white Power Macintosh G3 ("Bottom line: I like the machine") and John Siracusa's epic Mac OS X reviews. Everything else was right there on the front page for you to read.

Classic View isn't exactly like the Ars of 20 years ago. Our stories are longer on average than they were back then, so putting the entire text of all of our stories on each page would result in an insane amount of scrolling. Instead, Ars Pro subscribers will see headlines, lower deks (the brief summaries that accompany story headlines), and the first three paragraphs of each story.

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Steve McQueen’s Next Project: Thousands of School Photographs

NY Times - Tue, 2018-09-18 09:13
The artist and film director plans to collect pictures of about 115,000 children in London to try to capture the city’s diversity.

The Artist’s Life: What Happens When a Single Art Project Becomes a Decades-Long Obsession?

NY Times - Tue, 2018-09-18 09:11
Rodin and Duchamp toiled away on pieces for spectacular lengths of time. But in an era of digital hyperdrive, fidelity to one work seems even more heroic.

Amazon said to release eight new Alexa devices before year’s end

Ars - Tue, 2018-09-18 09:05

Alexa. Did he do it?

The world could have an Alexa-enabled microwave before 2018 is finished—yes, a microwave. According to a report by CNBC, Amazon may be gearing up to reveal up to eight new Alexa devices before the end of this year. Among those could be a microwave oven, a subwoofer, an amplifier, and an "in-car gadget." CNBC's report claims that an internal Amazon document points at the online retailer revealing some or all of these devices at an event scheduled for later this month.

All of the rumored devices would have Alexa built in, or have easy access to the virtual assistant (likely over an Internet connection). While the microwave oven would be new, Amazon has already partnered with companies like Sonos to make Alexa-enabled amplifiers and other audio equipment. The company also partnered with Garmin recently to make the Garmin Speak Plus, a dash cam that connects to Alexa for in-car voice commands.

It's unclear if the new devices will consist solely of collaborations between Amazon and other tech manufacturers, or if all of the devices will be made and sold by Amazon. The company's Echo family has grown a lot since the first Echo speaker debuted in 2014. Around this time last year, Amazon revealed the newest members of the Echo family: the Echo Spot and updated Echo speakers.

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Republicans want to run on Medicare. Democrats say bring it on.

Washington Post - Tue, 2018-09-18 09:02
The attacks are audacious but not new.

Opinion: In Syria, is the worst yet to come?

CNN - Tue, 2018-09-18 09:00
Bashar al-Assad thinks he is winning.

The Designers Envisioning a Bold New Kind of Japanese Architecture

NY Times - Tue, 2018-09-18 08:58
A freethinking firm makes its mark exploring the intersections between public and private, indoors and out, function and form.

US sailor killed in accident aboard aircraft carrier

CNN - Tue, 2018-09-18 08:57
A US Navy sailor was killed aboard the USS George H.W. Bush aircraft carrier on Monday afternoon, according to a statement from the Navy. The sailor was killed in an accident on the flight deck and the incident is currently under investigation.

Ice volcanoes have likely been erupting for billions of years on Ceres

Ars - Tue, 2018-09-18 08:55

Enlarge / Ahuna Mons, a likely cryovolcano. (credit: Dawn Mission, NASA, JPL-Caltech, UCLA, MPS/DLR/IDA)

All of the bodies in our Solar System started out hot, with energy built up by their gravitational collapse and subsequent bombardment. Radioactivity then contributed further heating. For a planet like Earth, that has kept the interior hot enough to sustain plate tectonics. Smaller bodies like Mars and the Moon, however, have cooled and gone geologically silent. That set the expectations for the dwarf planets, which were thought to be cold and dead.

Pluto, however, turned out to be anything but. It turns out that water and nitrogen ices need far less energy input to participate in active geology, and radioactive decay and sporadic collisions seem to be enough to sustain it. Which brings us to Ceres, a dwarf planet that is the largest body in the asteroid belt. The Dawn spacecraft identified an unusual peak called Ahuna Mons that some have suggested is a cryovolcano, erupting viscous water ice. But why would Ceres only have enough energy to support a single volcano?

A new paper suggests it doesn't. Instead, there may be more than two dozen cryovolcanoes on Ceres' surface. We just haven't spotted them because geology on the dwarf planet didn't stop when the cryovolcanoes stopped erupting.

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