Chapter 1. Biological Psychology: Scope and Outlook
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by Virginia Morell Elephants know when they need a helping hand—or rather, trunk. That's the conclusion of a new study that tested the cooperative skills of Asian elephants (Elephas maximus) in Thailand and showed that the pachyderms understand that they will fail at a task without a partner's assistance. The ability to recognize that you sometimes need a little help from your friends is a sign of higher social cognition, psychologists say, and is rarely found in other species. Elephants now join an elite club of social cooperators: chimpanzees, hyenas, rooks, and humans. To test the elephants' cooperation skills, a team of scientists modified a classic experiment first administered to chimpanzees in the 1930s, which requires two animals work together to earn a treat. If they don't cooperate, neither gets the reward. For the elephants, the researchers used a sliding table with a single rope threaded around it. Two bowls of corn were attached to the table, but the elephants could reach them only by pulling two ends of the rope simultaneously. Working with mahout—Asian elephant trainers—trained elephants at the Thai Elephant Conservation Center in Lampang, the researchers first taught individual animals to pull the rope with their trunks. The 12 elephants were then divided into six pairs, and each pair was released to walk to their waiting ropes. If one animal pulled the rope before the other, the rope would slip out, leaving the table—and treats—in place. "That taught them to pull together," says Joshua Plotnik, a postdoc in experimental psychology at the University of Cambridge in the United Kingdom and the lead author of the study, which appears online this week in the Proceedings of the National Academy of Sciences. © 2010 American Association for the Advancement of Science.
A new mouse model closely resembles how the human body reacts to early HIV infection and is shedding light on nerve cell damage related to the disease, according to researchers funded by the National Institutes of Health. The study in today’s Journal of Neuroscience demonstrates that HIV infection of the nervous system leads to inflammatory responses, changes in brain cells, and damage to neurons. This is the first study to show such neuronal loss during initial stages of HIV infection in a mouse model. The study was conducted by a team of scientists from the University of Nebraska Medical Center, Omaha, and the University of Rochester Medical Center, N.Y. It was supported by the National Institute on Drug Abuse (NIDA), the National Institute of Neurological Disorders and Stroke, the National Institute of Mental Health, and the National Center for Research Resources. "This research breakthrough should help us move forward in learning more about how HIV affects important brain functioning in its initial stages, which in turn could lead us to better treatments that can be used early in the disease process," said Dr. Nora D. Volkow, director of NIDA. "The work contained within this study is the culmination of a 20-year quest to develop a rodent model of the primary neurological complications of HIV infection in humans," said Dr. Howard Gendelman, one of the primary study authors. "Previously, the rhesus macaque was the only animal model for the study of early stages of HIV infection. However, its use was limited due to expense and issues with generalizing results across species. Relevant rodent models that mimic human disease have been sorely needed."
Link ID: 15064 - Posted: 03.03.2011
by Andrew Moseman Ken Jennings and Brad Rutter are accustomed to making others feel the heat as they blaze through Jeopardy clue after Jeopardy clue. But tonight, the quiz show's two greatest champions will oppose a player who can't be psyched out. It's time for the world to meet Watson. IBM's Jeopardy-playing computer system appears to viewers at home as an avatar of the Earth on a black screen. In fact, it is a system years in the making, and perhaps the most impressive attempt ever to create a question-answering computer that understands the nuances of human language. Watson is not connected to the Internet, but its databases overflow with books, scripts, dictionaries, and whatever other material lead researcher David Ferrucci could pack in. Storing information is the computer's strong suit; the grand artificial intelligence challenge of Jeopardy is the subtlety of words. advertisement | article continues below When the bright lights of Jeopardy go up tonight, there will be no human handler to tell Watson where inside its mighty databases to seek the answers. It must parse each clue and category title to figure out what it's being asked. It must race through its databases, find relevant search terms, and pick out the right response with a high level of confidence. It must understand the puns and geeky quirks of America's Favorite Quiz Show. It must beat two Jeopardy champions to the buzzer. And it too must voice its responses in the form of a question. © 2011, Kalmbach Publishing Co.
By TARA PARKER-POPE Researchers from the National Institutes of Health have found that less than an hour of cellphone use can speed up brain activity in the area closest to the phone antenna, raising new questions about the health effects of low levels of radiation emitted from cellphones. The researchers, led by Dr. Nora D. Volkow, director of the National Institute on Drug Abuse, urged caution in interpreting the findings because it is not known whether the changes, which were seen in brain scans, have any meaningful effect on a person’s overall health. But the study, published Wednesday in The Journal of the American Medical Association, is among the first and largest to document that the weak radio-frequency signals from cellphones have the potential to alter brain activity. “The study is important because it documents that the human brain is sensitive to the electromagnetic radiation that is emitted by cellphones,” Dr. Volkow said. “It also highlights the importance of doing studies to address the question of whether there are — or are not — long-lasting consequences of repeated stimulation, of getting exposed over five, 10 or 15 years.” Although preliminary, the findings are certain to reignite a debate about the safety of cellphones. A few observational studies have suggested a link between heavy cellphone use and rare brain tumors, but the bulk of the available scientific evidence shows no added risk. Major medical groups have said that cellphones are safe, but some top doctors, including the former director of the University of Pittsburgh Cancer Center and prominent neurosurgeons, have urged the use of headsets as a precaution. © 2011 The New York Times Company
Link ID: 15042 - Posted: 02.24.2011
Daniel Cressey In the past five years animal-rights activists have perpetrated a string of violent attacks. In February 2008, the husband of a breast-cancer biologist in Santa Cruz, California, was physically assaulted at the front door of their home. In the same month, the biomedical research institute at Hasselt University in Diepenbeek, Belgium, was set on fire. In the summer of 2009, activists desecrated graves belonging to the family of Daniel Vasella, then chief executive of the pharmaceutical company Novartis, based in Basel, Switzerland, and torched his holiday home. A poll of nearly 1,000 biomedical scientists, conducted by Nature, reveals the widespread impact of animal-rights activism. Extreme attacks are rare, and there does not seem to have been any increase in the rate of their incidence in the past few years, but almost one-quarter of respondents said that they or someone they know has been affected negatively by activism. More than 90% of respondents agreed that the use of animals in research is essential, but the poll also highlights mixed feelings on the issue. Nearly 16% of those conducting animal research said that they have had misgivings about it, and although researchers overwhelmingly feel free to discuss these concerns with colleagues, many seem less at ease with doing so in public. More than 70% said that the polarized nature of the debate makes it difficult to voice a nuanced opinion on the subject, and little more than one-quarter said that their institutions offer training and assistance in communicating broadly about the importance of animal research (see 'Assessing the threats'). © 2011 Nature Publishing Group,
Keyword: Animal Rights
Link ID: 15040 - Posted: 02.24.2011
US researchers defended animal testing, telling a small group at one of the biggest science conferences in the United States that not doing animal research would be unethical and cost human lives. The researchers, who are or have been involved in animal research, told a symposium at the annual meeting of the American Association for the Advancement of Science (AAAS) that testing on animals has led to "dramatic developments in research that have improved and affected the quality of human life." "To not do animal testing would mean that we would not be able to bring treatments and interventions and cures in a timely way. And what that means is people would die," Stuart Zola of Emory University, which is home to the Yerkes National Primate Research Center, told AFP after the symposium. Treatments for diseases such as diabetes and polio were made possible through animal research, the researchers said, and animals are currently being used in hepatitis-, HIV- and stem cell-related research, among others. But animal rights activists continue to bring pressure on laboratories that use animals to develop drugs and vaccines, urging them to stop the practice and use other means to develop the next wonder drug, treatment or cure. Animal rights activists also insist they will never use medications developed through animal testing, but the researchers said they probably already have done. © 2011 Discovery Communications, LLC.
Keyword: Animal Rights
Link ID: 15037 - Posted: 02.22.2011
by Michael Marshall When we look for examples of intelligent animals, certain species always leap to mind. Ourselves of course, and our close relatives the chimpanzees and other primates. Perhaps the cunning corvids – crows and scrub jays – with their prodigious memories and talent for deception. Dolphins and whales are pretty bright. Many would even agree that there is a sort of intelligence governing the behaviour of social insects like ants. But sheep? Sheep are just thick. Except that they aren't. Over the past few decades, evidence has quietly built up that sheep are anything but stupid. It now turns out that the humble domestic sheep can pass a psychological test that monkeys struggle with, and which is so sensitive it is used to look for neurological decline in human patients. Woolly thinkers Laura Avanzo and Jennifer Morton of the University of Cambridge were interested in a new kind of genetically modified sheep. These animals carry a defective gene that in humans causes Huntington's disease, an inherited disorder that leads to nerve damage and dementia. The hope is that the Huntington's sheep could be a testing ground for possible treatments. For that to work, they reasoned, researchers will have to be able to track changes in the cognitive abilities of the Huntington's sheep. So they decided to find out whether normal sheep could pass some of the challenging tests given to people with Huntington's. If the sheep passed, that would mean that the Huntington's sheep could be seen losing the ability as their disease progressed – and maybe regaining it if any treatments worked. © Copyright Reed Business Information Ltd.
Human brains have shrunk over the past 30,000 years, puzzling scientists who argue it is not a sign we are growing dumber but that evolution is making the key motor leaner and more efficient. The average size of modern humans -- Homo sapiens -- has decreased about 10 percent during that period -- from 1,500 to 1,359 cubic centimeters (91 to 83 cubic inches), the size of a tennis ball. Women's brains, which are smaller on average than those of men, have experienced an equivalent drop in size. These measurements were taken using skulls found in Europe, the Middle East and Asia. "I'd called that a major downsizing in an evolutionary eye blink," John Hawks of the University of Michigan told Discover magazine. But other anthropologists note that brain shrinkage is not very surprising since the stronger and larger we are, the more gray matter we need to control this larger mass. The Neanderthal, a cousin of the modern human who disappeared about 30 millennia ago for still unknown reasons, was far more massive and had a larger brain. The Cro-Magnons who left cave paintings of large animals in the monumental Lascaux cave over 17,000 years ago were the Homo sapiens with the biggest brain. They were also stronger than their modern descendants. Psychology professor David Geary of the University of Missouri said these traits were necessary to survive in a hostile environment. He has studied the evolution of skull sizes 1.9 million to 10,000 years old as our ancestors and cousins lived in an increasingly complex social environment. © 2011 Discovery Communications, LLC.
* Jonathan Leake LIFE really is unfair. Researchers have found that handsome men and beautiful women tend to be cleverer, with IQs averaging up to nearly 14 points above the norm. The finding, based on studies in Britain and America, suggests that the stereotype of blondes or good-looking men being dimmer than average needs to be revised. Instead it seems that evolution favours the already blessed, rewarding attractive people with partners who are not just good-looking but intelligent too. The research, by the London School of Economics, suggests that since both beauty and intelligence tend to be inherited, the children of such couples will end up with both qualities, building a genetic link between them. This link then becomes reinforced with successive generations. “Both in the British and American samples, physical attractiveness is significantly positively associated with general intelligence, both with and without controls for social class, body size, and health,” said Satoshi Kanazawa, the LSE researcher who carried out the research. “The association between physical attractiveness and general intelligence is also stronger among men than among women.” Dr Kanazawa found that in Britain men who are physically attractive have IQs an average 13.6 points above the norm, whereas physically attractive women are about 11.4 points higher than average. Copyright 2011 News Limited.
By Kirsten Traynor Intelligent people live longer—the correlation is as strong as that between smoking and premature death. But the reason is not fully understood. Beyond simply making wiser choices in life, these people also may have biology working in their favor. Now research in honeybees offers evidence that learning ability is indeed linked with a general capacity to withstand one of the rigors of aging—namely, oxidative stress. Ian Deary, a psychologist at the University of Edinburgh, has proposed the term “system integrity” for the possible biological link between intelligence and long life: in his conception, a well-wired system not only performs better on mental tests but is less susceptible to environmental onslaughts. Gro Amdam of Arizona State University and the Norwegian University of Life Sciences was intrigued by the idea and last year devised a way to test it in bees. Honeybees are frequently used as a neurobiological model for learning—they can be trained, using positive or negative reinforcement, to retain information. In Amdam’s experiment, individual bees were strapped into a straw, where they learned to associate an odor with a food reward in a classic Pavlovian conditioning scenario. After only one or two trials, many bees learned to stick out their tonguelike proboscis in anticipation of a sugary droplet. Some bees took a little longer—as in humans, there are quick learners and slower ones. © 2010 Scientific American,
Alison Abbott Animal activists last summer set fire to the alpine holiday home of Daniel Vasella, then chief executive of pharmaceutical giant Novartis of Basel, Switzerland, in one of relatively few violent attacks on scientists working with animals in German-speaking countries. But in the past few years these scientists have been feeling the pressure in other ways — from animal activists who have attempted to publicly shame them or have sent threatening e-mails, and from legislation that increasingly restricts the use of animals in basic research. Now, in a bid to reverse that trend, more than 50 top scientists working in Germany and Switzerland have launched an education offensive. Meeting in Basel on 29 November, they drafted and signed a declaration pledging to be more open about their research, and to engage in more public dialogue. "The public tends to have false perceptions about animal research, such as thinking they can always be replaced by alternative methods like cell culture," says Stefan Treue, director of the German Primate Center in Göttingen. Treue co-chaired the Basel meeting, called 'Research at a Crossroads', with molecular biologist Michael Hengartner, dean of science at the University of Zurich, Switzerland. Outreach activities, such as inviting the public into universities to talk to scientists about animal research, "will be helpful to both sides". © 2010 Nature Publishing Group
Keyword: Animal Rights
Link ID: 14753 - Posted: 12.07.2010
by James Garvey So long as people read Wittgenstein, people will read Peter Hacker. It’s hard to imagine how his work on the monumental Analytical Commentary on Wittgenstein’s Philosophical Investigations could possibly be superseded. He spent nearly twenty years on that project (ten of them in cooperation with his friend and colleague Gordon Baker), following in Wittgenstein’s footsteps, and producing a large number of important articles and books on topics in the philosophy of mind and language along the way. Nearer the end than the beginning of a distinguished career as an Oxford don, at a time of life when most academics would be happy to leave the lectern behind and collapse somewhere with a nice glass of wine, Hacker is in the middle of another huge project, this time on human nature. He also seems keen to pick a fight with almost anyone doing the philosophy of mind. This has a much to do with his view of philosophy as a contribution to human understanding, not knowledge. One might think that philosophy has the same general aim as science – securing knowledge of ourselves and the world we live in – even if its subject matter is more abstract and its methods more armchair. What is philosophy if not an attempt to secure new knowledge about the mind or events or beauty or right conduct or what have you? According to Hacker, philosophy is not a cognitive discipline. It’s something else entirely. “Philosophy does not contribute to our knowledge of the world we live in after the manner of any of the natural sciences. You can ask any scientist to show you the achievements of science over the past millennium, and they have much to show: libraries full of well-established facts and well-confirmed theories. If you ask a philosopher to produce a handbook of well-established and unchallengeable philosophical truths, there’s nothing to show.” © 2010 TPM: The Philosophers’ Magazine.
Link ID: 14638 - Posted: 11.08.2010
By Gregory Park , David Lubinski and Camilla P. Benbow Ninety years ago, Stanford psychologist Lewis Terman began an ambitious search for the brightest kids in California, administering IQ tests to several thousand of children across the state. Those scoring above an IQ of 135 (approximately the top 1 percent of scores) were tracked for further study. There were two young boys, Luis Alvarez and William Shockley, who were among the many who took Terman’s tests but missed the cutoff score. Despite their exclusion from a study of young “geniuses,” both went on to study physics, earn PhDs, and win the Nobel prize. How could these two minds, both with great potential for scientific innovation, slip under the radar of IQ tests? One explanation is that many items on Terman’s Stanford-Binet IQ test, as with many modern assessments, fail to tap into a cognitive ability known as spatial ability. Recent research on cognitive abilities is reinforcing what some psychologists suggested decades ago: spatial ability, also known as spatial visualization, plays a critical role in engineering and scientific disciplines. Yet more verbally-loaded IQ tests, as well as many popular standardized tests used today, do not adequately measure this trait, especially in those who are most gifted with it. Spatial ability, defined by a capacity for mentally generating, rotating, and transforming visual images, is one of the three specific cognitive abilities most important for developing expertise in learning and work settings. Two of these, quantitative and verbal ability, are quite familiar due to their high visibility in standardized tests like the Scholastic Aptitude Test (SAT). A spatial ability assessment may include items involving mentally rotating an abstract image or reasoning about an illustrated mechanical device functions. All three abilities are positively correlated, such that someone with above average quantitative ability also tends to have above average verbal and spatial ability. © 2010 Scientific American
by Adrian M Owen You might think it's obvious that one person is smarter than another. But there are few more controversial areas of science than the study of intelligence and, in reality, there's not even agreement among researchers about what this word actually means. Unlike weight and height, which are unambiguous, there is no absolute measure of intelligence, just as there are no absolute measures of honesty or physical fitness. Nonetheless, over the decades, legions of scientists have devised tests that can show that one person is smarter than another just as surely as Olympic events can shed light on how much you can lift or how far you can jump. Now my team at the UK Medical Research Council's Cognition and Brain Sciences Unit in Cambridge has come up with the ultimate test of intelligence. Like many researchers before us, we began by looking for the smallest number of tests that could cover the broadest range of cognitive skills that are believed to contribute to intelligence, from memory to planning. But we went one step further. Thanks to recent work with brain scanners, we could make sure that the tests involved as much of the brain as possible – from the outer layers, responsible for higher thought, to deeper-lying structures such as the hippocampus, which is involved in memory. Here's a longer explanation of the theory and evidence that we used when devising the tests. © Copyright Reed Business Information Ltd.
Thanks to better brain imaging and biological insights, we're closing in on the neurons of consciousness and the subtleties of our mental machinery Cognitive control Towards the seat of consciousness The question "what is consciousness?" represents one of the great frontiers of contemporary science. Thanks to studies of humans and animals, we now know that it is a subtly nuanced state whose nature and intensity varies according to the brain's intrinsic level of activity, its chemical microclimate and the information it receives from outside. By exploiting the normal vicissitudes of waking, sleeping and dreaming states, we are now beginning to explore how consciousness is expressed and controlled. For example, I have been involved in studies comparing brain activation in REM sleep with that in lucid-dreaming states, in which we retain much executive brain function. They seem to confirm the central importance of one specific area of the frontal brain - the dorsolateral prefrontal cortex - in regulating many key aspects of consciousness, including attention, decision-making and voluntary action. A combination of imaging techniques, judicious measures of subjective experience and detailed cellular and molecular-level studies will continue to deepen our understanding of our cognitive command centres in the coming years. With them we hope to crack the puzzle of consciousness, and perhaps correct the dysfunctional states of the brain we now call mental illness. Allan Hobson © Copyright Reed Business Information Ltd.
Link ID: 14556 - Posted: 10.16.2010
MIGRATORY bats have smaller brains than their stay-at-home cousins, suggesting they cannot afford the luxury of lugging large, energetically expensive brains on long journeys. The discovery might also be true for birds. The brains of migratory birds tend to be smaller than those of similar-sized species that do not migrate. But biologists have been unsure whether this is because non-migratory birds need larger brains to cope with the challenges of finding food through the changing seasons, or because migrators need to pare down their weight for travel. Larger brains burn more energy and their extra weight makes flight more costly too. Liam McGuire, an ecologist at the University of Western Ontario in London, Canada, and his colleague John Ratcliffe of the University of Southern Denmark in Odense turned to bats for the answer. Non-migratory species of bat typically hibernate through the winter months, so they do not need to adjust their foraging behaviour to survive. Yet the researchers still found that migratory bats had smaller brains than non-migratory ones (Biology Letters, DOI: 10.1098/rsbl.2010.0744). Other factors may also be important in birds, which show a greater difference in brain size than bats. But the finding suggests that the need to reduce weight in migrators is a sufficient evolutionary force to drive some of the difference. Issue 2780 of New Scientist magazine © Copyright Reed Business Information Ltd.
By Bruce Bower Rhesus monkeys typically don’t check themselves out in a mirror — unless they’re wearing funky acrylic forehead blocks attached to hair-thin electrodes implanted in their brains. Given that fashion-forward apparel, these monkeys avidly use mirrors to examine and groom their heads and to inspect hard-to-see body areas, say neuroscientist Luis Populin of the University of Wisconsin–Madison and his colleagues. Animals with head implants sometimes turned themselves upside down or adjusted mirrors to get a better view of out-of-the-way body parts, the scientists report in a paper published online September 29 in PLoS ONE. “Rhesus monkeys recognize themselves in the mirror and have some form of self-awareness,” Populin holds. As in previous studies, monkeys with colored marks on their faces failed to inspect the marks when provided with mirrors and sometimes made aggressive moves as if the marked reflection were another monkey. Researchers generally regard such behavior as showing a lack of self-awareness. Unlike facial marks, though, implanted head devices presented monkeys with a bodily change striking enough to trigger self-inspection with a mirror, Populin proposes. “It is hard to say what is going on, as the head implant is not only seen but felt by monkeys,” remarks psychologist Frans de Waal of Emory University in Atlanta. This new evidence supports the idea that monkeys recognize their own reflections as special and don’t misidentify the images as other monkeys, he says, even if it doesn’t establish that the animals have a concept of self (SN: 7/23/05, p. 53). © Society for Science & the Public 2000 - 2010
By Nathan Seppa The dismal range of options for treating a stroke might be improving. Scientists report that neutralizing an enzyme called NOX4 that shows up in stroke-damaged tissues can limit brain injury in mice. The study appears in the September PLoS Biology. Stroke treatment is often hampered because the primary available drug, a clot-buster called tPA, is effective only within three hours of a stroke’s onset; many strokes are not detected until after that window has closed. Knowing the molecular culprits involved in brain tissue damage caused by a stroke might give scientists another angle to exploit as they seek treatments, says Harald Schmidt, a physician and pharmacologist at Maastricht University in the Netherlands. To that end, Schmidt teamed with an international group of scientists to study the role of NOX4, a member of an enzyme family that makes free radicals — highly reactive molecules that can kill cells and contribute to tissue damage. The researchers induced strokes in mice by threading a filament up an artery into the brain to a point at which it obstructed the vessel. In a series of experiments, the scientists found that mice genetically engineered to lack the NOX4 enzyme showed substantially less damage from these strokes than mice making NOX4. In other tests, normal mice with the ability make the NOX enzymes fared better against strokes when given an experimental drug that neutralized NOX4 than did mice not receiving the drug. © Society for Science & the Public 2000 - 2010
Link ID: 14483 - Posted: 09.23.2010
By CLAUDIA DREIFUS Q. DID CHILDHOOD VIEWING OF THE “FLIPPER” TELEVISION SERIES MAKE YOU WANT TO BECOME A DOLPHIN RESEARCHER? A. No, it was The New York Times! In the 1970s, I was working as a set designer for an avant-garde theater company in Philadelphia. One Sunday, I read The Times and saw this photograph of a baby whale being killed. Something in me just snapped. “It’s a shame we’re slaughtering these animals when we know so little about them,” I said. I then got a Ph.D. I’ve been devoting myself to studying the abilities and the behaviors of whales and dolphins since. Q. DOLPHINS SPEND MUCH OF THEIR LIVES UNDERWATER. HOW CAN YOU OBSERVE THEIR BEHAVIOR? A. Well, I observe captive dolphins in aquariums. At the moment, my laboratory is an underwater glass booth in the dolphin pool at the National Aquarium in Baltimore. I climb into it with a video camera. The animals are used to me. My goal is to understand their behaviors well enough so that I can find ways to help them tell us about their cognitive capacities. Dolphins, they have these really large, complex brains. The question is: what are they doing with them? These animals look like fish, but the behavior patterns are more like primates and elephants. They are vocal learners, like parrots and humans. What do the sounds they make mean? Copyright 2010 The New York Times Company
By Larry O'Hanlon There are theories galore about why some dog breeds appear to be smarter than others, but new research suggests that size alone might make a difference. All larger dogs appear to be better at following pointing cues from humans than smaller dogs, which makes them appear smarter. It's possible that bigger dogs appear smarter not just because they are bred for taking orders, but because their wider set eyes give them better depth perception. As a result, they can more easily discern the direction a person is pointing. This latter hypothesis was tested by researchers in New Zealand, who think there might be something to it. "We do know that dog breeds are different," said William Helton of the University of Canterbury in Christchurch, New Zealand. Human breeding has created dogs with huge physical differences, like shorter snouts for more powerful bites. Even the internal structure of dogs eyes can vary among some breeds, he said. But can something as simple as the distance between the eyes be a factor too? To see if all larger dogs in general were better at discerning human pointing cues, Helton and his colleagues put 104 dogs to the test -- 61 large dogs (greater than 50 lbs) and 43 small dogs (less than 50 lbs). © 2010 Discovery Communications, LLC.