A new experiment on the emission spectrum of quantum dots in photonic-crystal microcavities supports a recently proposed theory of cavity quantum electrodynamics.
A water wave incident on a grooved wall is shown to be analogous to electromagnetic waves called surface plasmon polaritons.
The ability of metamaterials to steer light has enabled amazing inventions from superresolution microscopes to “invisiblity” cloaks. But the physics underlying these structures also applies to other waves, such as acoustic, seismic, and water waves. Huanyang Chen and his colleagues at Xiamen University in China have demonstrated a structure that can change the propagation of surface water waves, making a localized wave that is analogous to an electromagnetic excitation called a surface plasmon polariton [1].
Surface plasmon polaritons occur at the interface between a dielectric and a negative-permittivity material such as a metal. Generating an equivalent excitation in surface water waves requires a similar sort of interface, such as that between water and a vertical barrier. In this case, the water’s parameter that is analogous to a metal’s permittivity is its depth. Of course, it’s impossible for water to have negative depth, but using metamaterials, Chen and his colleagues engineered the boundary conditions of the waves to achieve the same effect.
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TOKYO, May 24 (Reuters) — President Joe Biden on Tuesday said there was no change to a U.S. policy of “strategic ambiguity” on Taiwan, a day after he angered China by saying he would be willing to use force to defend the democratic island.
The issue of Taiwan loomed over a meeting in Tokyo of leaders of the Quad grouping of the United States, Japan, Australia and India, who stressed their determination to ensure a free and open Indo-Pacific region in the face of an increasingly assertive China — though Japanese Prime Minister Fumio Kishida said the group was not aimed at any one country.
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Experts believe AGI will occur around 2050, and plausibly sooner. You can see above their estimates regarding specific AI achievements: passing the Turing test, passing third grade, accomplishing Nobel worthy scientific breakthroughs and achieving superhuman intelligence.
A theoretical physicist has outlined how mankind could build a giant spinning space settlement in orbit around Ceres. It involves a space elevator.
The virus is called monkeypox because researchers first detected it in laboratory monkeys in 1958, but it is thought to transmit to people from wild animals such as rodents or from other infected people. In an average year, a few thousand cases occur in Africa, typically in the western and central parts of the continent. But cases outside Africa have previously been limited to a handful that were associated with travel to Africa or with the importation of infected animals. The number of cases detected outside of Africa in the past week alone — which is almost certain to increase — has already surpassed the total number detected outside the continent since 1970, when the virus was first found to cause disease in humans. This rapid spread is what has scientists on high alert.
But monkeypox is no SARS-CoV-2, the coronavirus responsible for the COVID-19 pandemic, says Jay Hooper, a virologist at the US Army Medical Research Institute of Infectious Diseases in Fort Detrick, Maryland. It doesn’t transmit from person to person as readily, and because it is related to the smallpox virus, there are already treatments and vaccines on hand for curbing its spread. So although scientists are concerned — because any new viral behaviour is worrying — they are not panicked.
Unlike SARS-CoV-2, which spreads through tiny air-borne droplets called aerosols, monkeypox is thought to spread from close contact with bodily fluids, such as saliva from coughing. That means a person with monkeypox is likely to infect far fewer close contacts than someone with SARS-CoV-2, Hooper says. Both viruses can cause flu-like symptoms, but monkeypox also triggers enlarged lymph nodes and, eventually, distinctive fluid-filled lesions on the face, hands and feet. Most people recover from monkeypox in a few weeks without treatment.
The bottom of the ocean is full of mysteries but scientists have recently uncovered one of its best-kept secrets. For 25 years, drug hunters have been searching for the source of a natural chemical that had shown promise in initial studies for treating cancer. Now, researchers at University of Utah Health report that easy-to-find soft corals—flexible corals that resemble underwater plants—make the elusive compound.
Identifying the source allowed the researchers to go a step further and find the animal’s DNA code for synthesizing the chemical. By following those instructions, they were able to carry out the first steps of re-creating the soft coral chemical in the laboratory.
“This is the first time we have been able to do this with any drug lead on Earth,” says Eric Schmidt, Ph.D., professor of medicinal chemistry at U of U Health. He led the study with Paul Scesa, Ph.D., postdoctoral scientist and first author, and Zhenjian Lin, Ph.D., assistant research professor.
Thought Machine CEO Paul Taylor was the brains behind Google’s text-to-speech technology. He now runs the company on the same principles learnt in his early career at Google.
An image from the Hubble Space Telescope shows an unusual interaction of four dwarf galaxies, so close together that all of them would fit within the Milky Way.
An image from the Hubble Space Telescope shared this week by NASA shows an unusual interaction of four dwarf galaxies. There are two small galaxies which are so close together that they look like one object, called NGC 1,741, located at the top of the image. Then there is another cigar-shaped galaxy close by to the right, and a fourth galaxy in the bottom left which is connected to the other three by a stream of young stars.
Together, the four galaxies make up a set called the Hickson Compact Group 31, or HCG 31. The group is located 166 million light-years away from Earth, which is relatively close for seeing interacting dwarf galaxies. The galaxies are currently so close together, at within 75,000 light-years of each other, that all four of them would fit within the Milky Way.
Researchers have discovered that Clostridium septicum rapidly kills cells by releasing a toxin that punches holes in the surface of the cell. This induces an immune response that can lead to sepsis and shock. The team is now exploring whether it’s possible to develop drugs to neutralize the toxin to treat the infection.
