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Acoustic levitation allows small objects, like droplets of liquid, to float. Unless you travel into the vacuum of space, sound is all around you every day. But most of the time, you probably don't think of it as a physical presence. You hear sounds; you don't touch them. The only exceptions may be loud nightclubs, cars with window-rattling speakers and ultrasound machines that pulverize kidney stones. But even then, you most likely don't think of what you feel as sound itself, but as the vibrations that sound creates in other objects. The idea that something so intangible can lift objects can seem unbelievable, but it's a real phenomenon. Acoustic levitation takes advantage of the properties of sound to cause solids, liquids and heavy gases to float. The process can take place in normal or reduced gravity. In other words, sound can levitate objects on Earth or in gas-filled enclosures in space. Treating back and neck pain with spinal traction is a practice that's been around for many years. As with many medical treatments, this method has evolved with technology, but the rationale and the effects remain the same. The goal of spinal traction is to pull the vertebrae apart from each other. The purpose is generally to create more space for nerves where they exit the spinal column or to relieve pressure on the cartilage disks between the bones or on the small spinal joints themselves. At lower intensities, it can also be used to stretch small spinal muscles. The unproven theory is that if the disks are pulled, they will regain hydration or have an influx of water. This would then make them more shock absorbent. What we do know is how much force of pull is needed to get certain areas of the spine to separate between segments. In the cervical spine (neck) it takes about 20-30 pounds of pull to achieve separation. dia de la independencia de mexico

















































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