New Worlds: New technique adds magnesium to desalinated water

Current techniques produce water lacking calcium, magnesium and other minerals vital to health.

By JUDY SIEGEL-ITZKOVICH
tap water 88 (photo credit: )
tap water 88
(photo credit: )
A new technique that cheaply introduces healthful magnesium ions to desalinated water has been developed by the Technion-Israel Institute of Technology. All desalinated water in Israel is produced by reverse osmosis, in which salt water from the sea is passed through membranes that separate the salts out. This produces water lacking calcium, magnesium and other minerals vital to health. The lack of magnesium can be harmful not only to humans but also to agricultural plants. To deal with this problem, calcium and other chemicals are added to Israeli desalinated water. But magnesium is not added because of the high cost. In the cheaper new technique, the Technion researchers take magnesium ions from the sea and "charge" them into desalinated water at concentrations recommended by the World Health Organization. Researchers in the institute's civil and environmental engineering faculty filed a patent for this process, which is more environmentally friendly than the conventional system. The concentration of magnesium ions in seawater is five times that of calcium ions, according to Dr. Uri Lahav, who developed the technique that takes advantage of this. In a few months, a semi-industrial plant will be set up adjacent to the small desalination plant at Kibbutz Ma'agan Michael to try out the process in the field. It is expected to supply 400 to 1,000 cubic meters of mineral-enriched desalinated water per day. The new process will be presented at the upcoming conference of the Israel Water Association. ISRAELIS WIN HONORS AT MATH COMPETITION The team representing Israel in the SEEMOUS 2008 international mathematics competition held recently in Athens brought home high honors. Six members of the Israeli contingent came back with medals - two silver and four bronze - thus winning fourth place after the Ukraine, Russia and Romania. The competition is meant for bachelor's degree graduates in mathematics from around the world. Some 100 finalists participated. Among the outstanding Israelis were Alexei Geldkich of Tel Aviv University and Amos On of the Open University. They were trained on a voluntary basis by math whizzes and assisted by the Israel Mathematics Society. TOPS IN BIOLOGY Meanwhile, a teenage girl from Hadera has won top prize at the annual Biology Olympics Competition for Youth held at Bar-Ilan University. Anat Skliar will receive a year's scholarship at BIU for her accomplishment. Some 170 pupils from around the country competed. Two boys, Yishai Netzer of Kfar Saba and Gild Tal of the Emek Ha'maaravi School, who took the second and third prize, will receive partial scholarships from Teva Pharmaceuticals. The 170 contestants were tested on their understanding of scientific articles on ecology, while 30 finalists prepared posters describing an ecological problem or another research problem they investigated. A biological photo competition accompanied the biology quiz. BRAIN PLAYS TRICKS ON VISION There are two separate visual systems in the brain, and they can play tricks. New research at Ben-Gurion University of the Negev suggests that we process images in two distinct ways. "The idea of two visual systems in a single brain might seem counter-intuitive. After all, it seems obvious that it is the same subjective image that allows us both to recognize a coffee cup on our desk and pick it up," writes BGU psychologist Dr. Tzvi Ganel. But when there is a conflict between what we perceive and what really exists, our fingers have an advantage. Ganel and colleagues tested individuals using the "Ponzo" illusion" - an image that makes two objects similar in length appear drastically different. They then hooked participants' index fingers and thumbs to computerized position-tracking equipment and asked them to grasp the objects. The size of their grasp reflected the object's real size. This research was published in the March issue of Psychological Science, a journal of the Association for Psychological Science. As Ganel points out, these findings provide compelling support for what psychologists and neuroscientists describe as the "two visual systems hypothesis." According to this theory, put forward more than a decade ago by Mel Goodale and David Milner, one system, called vision-for-perception, gives us our conscious visual experience of the world, allowing us to see objects in context. It's also the one that is fooled by optical illusions. The other system, called vision-for-action, provides the visual control we need to interact with objects. This system does not have to be conscious, but must be quick, goal-directed and accurate - and as a consequence is much less likely to be fooled by illusions.