Artificial sweeteners are used by millions of Britons to cut their calorie intake and lower sugar consumption.
The thinking is that these sweeteners, which have few or no calories, are better for the waistline and don’t increase blood sugar levels.
However, research suggests one of the most popular stevia may not be good for our gut bacteria, which play a key role in a host of functions including immunity and mood.
Artificial sweeteners, which can be added to drinks or sprinkled over food, include sucralose, aspartame, saccharin, and the sugar alcohols xylitol and erythritol.
There have been suggestions from animal studies that sweeteners generally ‘trick’ the brain, increasing your appetite the brain thinks the body is processing sugar, but it’s not getting the energy it expects, so makes you eat more
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Antarctica is often perceived as nothing more than a lifeless barren of cold. A frozen dessert. However, not many are aware of the booming and flourishing population of Weddel seals that dominated the waters of the frozen south. There, they create a soundscape that a lot of creatures, especially humans, are unaware of.
(Photo : Vassil Tzvetano on Wikimedia Commons)
These pinnipeds typically emit high-pitched pings that sound like laser guns in a science-fiction movie. But that is not their entire repertoire. Research reveals that a significant portion of their calls is at ultrasonic frequencies, high pitches well beyond the 20-kilohertz limit of most human hearing.
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Weddell seals use a breathing hole in the frozen surface of the Ross Sea. Credit: Alasdair Turner
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Above the frozen ocean, Antarctica can be eerily quiet. Gusts of wind are often all one hears. Below, though, the Southern Ocean is a living soundscape dominated by Weddell seals. These pinnipeds typically emit high-pitched pings that sound like laser guns in a science-fiction movie. But that is not their entire repertoire. Research now reveals that a significant portion of their calls are at ultrasonic frequencies, high pitches well beyond the 20-kilohertz limit of most human hearing.
University of Oregon marine biologist Paul Cziko installed a livestreaming audio and video system at Antarctica’s McMurdo Station in 2017, allowing scientists to listen in on the massive mammals’ underwater calls. Data from the setup yielded surprising results: The seals sometimes vocalized at extremely high, ultrasonic frequencies of more than 200 kilohertz, Cziko and his coll
Detecting the presence of an unmanned underwater vehicle (UUV) is usually achieved by intercepting the noise radiated by its propeller. In a noisy harbor, this task is hindered because the acoustic signature of a UUV and the noise in the local environment often present too much signal complexity for current technologies to process.
That may be about to change. Researchers at Draper, Massachusetts Institute of Technology (MIT) and Woods Hole Oceanographic Institute (WHOI) have developed an acoustic remote sensing method for high-precision propeller rotation and speed estimation of unmanned underwater vehicles.
The new method is detailed in a study published in the Journal of the Acoustical Society of America.
How Unmanned Underwater Vehicles Could Become Easier to Detect
Detecting the presence of an unmanned underwater vehicle (UUV) is usually achieved by intercepting the noise radiated by its propeller. In a noisy harbor, this task is hindered because the acoustic signature of a UUV and the noise in the local environment often present too much signal complexity for current technologies to process.
That may be about to change. Researchers at Draper, Massachusetts Institute of Technology (MIT) and Woods Hole Oceanographic Institute (WHOI) have developed an acoustic remote sensing method for high-precision propeller rotation and speed estimation of unmanned underwater vehicles.