Where and how to grab space debris
Objects in space tend to spin – and spin in a way that’s totally different from the way they spin on Earth. Understanding how objects are spinning, where their centers of mass are, and how their mass is distributed is crucial to any number of actual or potential space missions, from cleaning up orbiting satellite debris to landing a demolition crew on a comet.
In an coming issue of the Journal of Field Robotics, Massachusetts Institute of Technology researchers will describe a new algorithm for gauging the rotation of objects in zero gravity using only visual information. And at the International Conference on Intelligent Robots and Systems this week, they will report the results of experiments in which they tested the algorithm aboard the International Space Station. On all but one measure, their algorithm was very accurate.
“There are thousands of pieces of broken satellites in space,” said MIT astronautics scientist Alvar Saenz-Otero. “If you were to send a super-massive spacecraft up there ... it would cost lots of money. But if you send a small spacecraft, and you try to dock to a small, tumbling thing, you also are going to start tumbling. So you need to observe that thing that you know nothing about so you can grab it and control it.” newsoffice.mit.edu
Brain maps decode how we aim at objects
Serena Williams won her third consecutive U.S. Open title a few days ago, thanks to reasons including obvious ones like physical strength and endurance. But how much did her brain functions help the American tennis star retain the cup?
Quite significantly, according to neuroscience researchers at Toronto’s York University. Their recent study, published in the Journal of Neuroscience, shows that different regions of the brain help to visually locate objects relative to one’s own body (self-centered or egocentric) and those relative to external visual landmarks (world-centered or allocentric).
The study was conducted using the state-of-the-art fMRI scanner.
The study “shows how the brain encodes allocentric and egocentric space in different ways during activities that involve manual aiming,” explained Doug Crawford, a psychology professor at York. “Take tennis for example. Allocentric brain areas could help aim the ball toward the opponent’s weak side of play, whereas the egocentric areas would make sure your muscles return the serve in the right direction.”
The findings will help health care providers develop therapeutic treatment for patients with brain damage in these two areas, according to neuroscientists at York Centre for Vision Research. news.yorku.ca
Can blood type affect memory loss?
People with blood type AB may be more likely to develop memory loss in later years than people with other blood types, according to a study published in the online issue of Neurology, the medical journal of the American Academy of Neurology.
AB is the least common blood type, found in about 4 percent of the U.S. population. The study found that people with AB blood were 82 percent more likely to develop the thinking and memory problems that can lead to dementia than people with other blood types. Previous studies have shown that people with type O blood have a lower risk of heart disease and stroke, factors that can increase the risk of memory loss and dementia.
“Blood type is also related to other vascular conditions like stroke, so the findings highlight the connections between vascular issues and brain health,” said study author Mary Cushman of the University of Vermont College of Medicine. aan.com