New World: New light on solar energy

New World New light on

A new type of glass cell that absorbs solar energy and concentrates it so it converts into electricity more efficiently than conventional solar panels by taking only the radiation without the heat has been developed by Prof. Renata Reisfeld, longtime expert in sol-gel glasses at the Hebrew University's inorganic chemistry department. It can absorb solar energy even on a cloudy day without direct sunlight - albeit less efficiently than on a sunny day. Reisfeld, who is chief technology officer of the GreenSun company that is working to commercialize the product, developed it in her Jerusalem laboratory. The glass cell panels, made in bright colors, concentrate the light in the center of the glass plate and thus is cheaper than conventional ones because it needs silicone only there rather than on the whole panel. The plates absorb specific parts of the light spectrum of the sun, Reisfeld says, adding that they can lie on a roof and absorb dispersed light without facing the sun most of the day. The heat from solar radiation in fact damages the cells, says the inorganic chemist, so the new technique intentionally causes the heat to be dispersed. Walls and windows could be made out of the glass to turn a building into a power generator on the outside. However, some experts say that using the technology will hike construction expenses, as it is more expensive than conventional building materials. In addition, the panels' efficiency is not yet high enough to be used routinely. GETTING TO THE TRUTH Graphologists have long claimed to be able to examine handwriting and surmise whether the writer is telling the truth or not, but now a University of Haifa team has developed and tested a computerized system claimed to accurately accomplish this. The work by Dr. Gil Luria of the human services department and Dr. Sara Rosenblum of the occupational therapy department revealed distinct differences between truthful and false content in the flow of writing, the height and length of strokes and even in pen pressure on the page. Various cognitive characteristics in falsehood that are handwritten are distinctly different from those that are exposed in truthful writing, they maintain. "It seems that the act of writing a false text involves extensive cognitive resources and the automatic act of writing is thereby affected," they said. Despite the need and desire that most people have to identify lies, it has always been a difficult and complex task. Available tools such as the polygraph are still problematic. While the polygraph attempts to identify physiological changes, the current study has examined whether the act of lying causes cognitive changes. This approach is based on the assumption that writing lies requires special resources and causes cognitive stress, which in turn affects performance that would otherwise be carried out automatically. The participants in the study were asked to write two paragraphs. First they were told to describe an event that really took place and then to give a description of an event that did not really occur. The participants wrote the paragraphs with an electronic pen on a page that was placed on an electronic board. The data was analyzed with the help of a program that Rosenblum developed a few years ago. The system is able to garner data that cannot be measured manually, such as pressure, rhythm and speed, duration and frequency. The study revealed that pressure on the page when writing deceptive content is significantly heavier than when writing the truth. Likewise, the flow of strokes when writing false text, as expressed in the height and length of the letters, is distinctly different from these elements in truthful writing. According to the researchers, the results of the study show that when writing a lie, otherwise automatic acts become more controlled by the brain and consequently performance is altered, which is expressed in the size, duration and pressure of the false writing."A lie detector that analyzes handwriting has many advantages over the existing detectors, since it is less threatening for the person being examined, is much more objective and does not depend on human interpretation," they said. DOGGONE GENES Data from Portuguese water dogs - the breed represented at the White House in the form of a dog named Bo to suit Barack Obama's allergy-prone daughter Malia - have been used to find a gene that gives some dogs curly hair and others long, wavy hair. The University of Utah study was part of work at the US National Institutes of Health published recently by the journal Science - showing that variations in only three genes account for the seven major types of coat seen in purebred dogs. The findings also point the way toward understanding complex human diseases caused by multiple genes. "We were part of a team that found three genes that control 90 percent of the seven coat types that characterize different breeds of purebred dogs," said biology Prof. K. Gordon Lark, one of 20 coauthors of the study. "We helped identify the gene that controls curly or wavy coats," adds study coauthor biology Prof. Kevin Chase. They found that combinations of various forms of only three genes - named RSPO2, FGF5 and KRT71 - account for seven major coat types in purebred dogs. By analyzing more than 1,000 dogs from 80 domestic breeds, the researchers found that RSPO2 is the gene associated with whether or not a dog has a moustache and large eyebrows (known together as "furnishings"); FGF5 is linked to whether a dog's fur is long or short; and KRT71 determines if the hair is curly. All purebred dogs have the three genes, but the presence or absence of mutant, variant forms of those genes - rather than the ancestral forms inherited from wolves - determines coat types: Short-haired dogs like basset hounds have none of the variant genes, just the ancestral form of each gene. Wire-haired dogs such as Australian terriers have the variant form of only the RSPO2 gene. Dogs with wiry and curly hair - airedale terriers, for example - have variants of both RSPO2 and KRT71 genes. Long-haired dogs like golden retrievers have a variant form of the FGF5 gene. Long-haired dogs with furnishings, such as the bearded collie, have variant forms of FGF5 and RSPO2. Curly haired dogs such as Irish water spaniels have the variant forms of the FGF5 and KRT71 genes. Curly haired dogs with furnishings - such as the bichon frise breed and some Portuguese water dogs, including Bo - have the variant form of all three genes.