In many parts of the world invasive species contribute to destruction of local ecosystems, already threatened by climate change. One of the most pervasive is the lionfish, a voracious predator from Asia that is depleting native coral reef fish in the Caribbean. Now, a new underwater robot is showing off a way that technology can help on the front line fight against invasive species. VOA’s George Putic reports.
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Day: April 25, 2017
A strong earthquake of magnitude 6.9 struck off the west coast of Chile on Monday, rocking the capital Santiago and briefly causing alarm along the Pacific Coast but sparing the quake-prone nation of any serious damage.
The quake was centered about 85 miles (137 km) from Santiago, and some 22 miles (35 km) west of the coastal city of Valparaiso. The U.S. Geological Survey twice revised the magnitude before settling on 6.9, a strength usually capable of causing severe damage.
The epicenter’s shallow depth of 15.5 miles (25 km) below the sea allowed it to be felt hundreds of miles (km) away.
Santiago office buildings swayed for about 30 seconds at the end of the workday.
‘Short, but very powerful’
Closer to the epicenter, residents scrambled for higher ground, remembering the lessons of the country’s devastating earthquake and tsunami in 2010.
“It was short but very powerful,” said Paloma Salamo, a 26-year-old nurse, who was in a clinic in Viña del Mar, just north of Valparaiso, when the quake struck.
People ran from the facility carrying children and some headed for the hills when the tsunami alarm sounded, she said, but calm was soon restored.
“So far there has been no human loss nor significant damage,” President Michelle Bachelet said, praising people for evacuating in an orderly fashion in the immediate aftermath.
Cellphone networks down
Officials canceled a tsunami warning that had been issued in Valparaiso. The Pacific Tsunami Warning Center reported small tsunami waves of half a foot (15 cm).
There were no reports of structural damage in Valparaiso, but cellphone networks were down in some places, a spokesman with the local government said.
Videos from the Valparaiso area showed objects falling from store shelves, rocks falling onto roads and lights flickering.
Felt beyond the Andes
The quake was felt as far away as Argentina, on the other side of the Andes.
Interior Minister Mario Fernandez said there had been some landslides but “in general the situation is pretty normal bearing in mind the quake’s intensity.”
Strict construction codes in Chile limit damage to buildings.
Copper mining was unaffected, according to Chile’s state-run Codelco, one of the largest copper mining companies in the world, and Anglo American, which has copper operations in central Chile.
But interruptions in the electricity supply led the Aconcagua oil refinery to temporarily suspend operations for safety reasons, state-run oil firm ENAP said. There was no damage to either of Chile’s two refineries, ENAP said.
Several aftershocks including two of magnitudes 5.0 and 5.4 were recorded in the same spot and could be felt in Santiago, part of a cluster of tremors from that area in recent days.
‘Ring of Fire’
Chile, located on the so-called “Pacific Ring of Fire,” has a long history of deadly quakes, including a 8.8 magnitude quake in 2010 off the south-central coast, which also triggered a tsunami that devastated coastal towns. More than 500 people died.
That was the sixth-largest earthquake ever recorded, according to the USGS. The largest recorded temblor in history was also in Chile, a 9.5-magnitude quake in 1960.
The long, slender country runs along the border of two tectonic plates, with the Nazca Plate beneath the South Pacific Ocean pushing into the South America Plate, a phenomenon that also formed the Andes Mountains.
An experimental blood test can quickly and accurately diagnose malaria from other infections, so treatment of the mosquito-borne illness can be started promptly.
The symptoms of malaria, which strikes an estimated 200 million people around the globe every year, are non-specific. That means the fever, aches, pains and chills in the early stages could be mistaken for any number of infections.
Identifying and treating malaria promptly not only increases a patient’s chances of survival, but also helps prevent the disease from spreading to more people.
The blood test, developed by researchers at Stanford University in California, looks for patterns of immune system activation to determine whether a person is infected with the malaria parasite, and not a bacterium or virus. It is reportedly 96 percent accurate.
Purvesh Khatri, a professor of medicine at Stanford, helped develop the biomarker test, which looks at which genes are switched on or off, depending on the infection.
A simple blood test measuring these immune markers could be helpful in resource-poor settings, according to Khatri.
“So a test like ours is useful,” he said, “You could take a blood test that would not require an expert technician, and they are more sensitive than the rapid diagnostic test than we have now.”
Khatri notes the current test is not very accurate because it looks for a molecule, called an antigen, that activates an immune response in a malaria infection.
“And the problem with those are there are not enough antigen,” said Khatri. “So treatment then [could] be inappropriate and then it could awhile before malaria is diagnosed.”
Khatri and his team drew upon data from 40 studies involving more than 3,000 blood samples from patients with various infections. Some were known to have malaria. But there were also other tropical illnesses observed in the studies, including dengue, typhoid and leishmaniasis.
From those blood studies, investigators analyzed the activation of 2,100 different genes, looking at which genes switched on and off with parasitic, viral and bacterial infections.
They found a group of seven genes that were expressed in malaria compared to healthy people and those with other infectious illnesses.
To confirm their discovery, the researchers whittled the samples down to 900, in which they were able to discern the pattern of gene activation unique to malaria with near 100 percent accuracy.
While the experimental blood test is accurate in diagnosing malaria, Khatri says it might also detect other parasitic diseases that researchers have not yet studied.
But he said the blood test could be reliably used in cases where malaria is strongly suspected and confirmation of the disease is needed.
Khatri presented his findings at a meeting of the European Congress of Clinical Microbiology and Infectious Diseases before World Malaria Day this week.
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Nine years after his death at age 28, audiences are seeing a different side of Australian actor Heath Ledger through the lens of his own camera.
Documentary “I Am Heath Ledger” uses thousands of hours of self video shot by Ledger, as well as his art work and music videos, to paint a portrait of the young actor who took Hollywood by storm in roles like “Brokeback Mountain” and “The Dark Knight.”
The film also seeks to counteract the lingering perception that Ledger was severely depressed when he accidentally overdosed on painkillers, anxiety and insomnia medication.
“He was super happy and he was loving life. He struggled with some demons, but he wasn’t one to go anywhere but forward,” Ledger’s Hollywood agent Steve Alexander says in the film, which was launched at the Tribeca Film Festival this week.
Rather than dwell on his January 2008 death in New York, the film uses Ledger’s video archives and interviews with his family and closest friends to “celebrate Heath’s life and to tell the story of this multi-faceted artist,” director and producer Derik Murray told Reuters Television.
It portrays Ledger as a force of nature who longed for adventure, was generous with his friends, and whose passions ranged from chess to making music videos. His non-stop energy also meant he rarely slept a full night.
While Ledger’s friends including Naomi Watts and director Ang Lee were interviewed for the film, Michelle Williams’ – Ledger’s former fiance and mother of his daughter Matilda – chose not to take part, said her spokeswoman.
Murray said Williams’ support was integral to the film “but she really didn’t feel she wanted to be in front of the camera.”
Ledger was found dead a few months after the couple split up and shortly after filming his role as the manic Joker in “The Dark Knight,” for which he won a posthumous Oscar.
“There was a lot of conversation and chatter around the fact that his passing was a byproduct of his role as the Joker and that he spiraled down this path and couldn’t pull himself out of it,” said Murray.
But Murray said everyone the filmmakers spoke to said this was untrue. “He had the best time making it… The Joker was a role. He was enthralled by it. He was proud of it.”
“I Am Heath Ledger” will get a one-night showing in 300 U.S. movie theaters on May 3 and premiere on Spike TV on May 17.
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