Headline of the day
Dr. Kevorkian says that "everyone should refuse to vote" (The Obscure Store)
So, how does a golden retriever say “I think Tarantino’s overrated”?
Scientists develop computer that can 'translate' a dog's bark
What would a dog say if it could talk? "Stranger", "fight", "walk", "alone", "ball" and "play", according to scientists who have developed a computer programme to translate dog barks.
The special programme analysed more than 6,000 barks from 14 Hungarian sheepdogs in six different situations.
In a series of tests the team of scientists, from Eötvös Loránd University in Hungary led by Csaba Molnár, discovered that a computer could recognise whether a dog was in a stranger, fight, walk, alone, ball or play scenario.
The barks were tape recorded and then digitized on a computer, which used software to study their differences.
The computer correctly identified the different situations 43 per cent of the time. Although it was not a high success rate it was far better than human recognition, the researchers said.
The computer was most accurate in identifying the "fight" and "stranger" contexts, and was least effective at matching the "play" bark.
The results appear in the journal Animal Cognition, and suggest that dogs have acoustically different barks depending on their emotional state.
The researchers also performed a second test, in which the computer identified individual dogs by their bark.
The software correctly identified the dogs 52 per cent of the time, again much better than the human result, suggesting there are individual differences in barks even though humans are not able to recognize them.
The team also plans to compare the barks of different breeds to discover what they have in common.
“Food Insecurity.” This is what you get when eggheads cannot pronounce the words “poor folks go hungry.”
Food Insecurity Associated With Developmental Risk In Children
ScienceDaily (Jan. 16, 2008) — Researchers from Boston University School of Medicine (BUSM) and Boston Medical Center (BMC), in collaboration with researchers from Arkansas, Maryland, Minnesota and Pennsylvania, have found that children living in households with food insecurity , are more likely to be at developmental risk during their first three years of life, compared to similar households that are not food insecure.
The U.S. Department of Agriculture estimates that 16.7 percent of all U.S. households with children less than six years of age had food insecurity in 2005, reporting limited or uncertain availability of enough food for an active healthy life. In children aged less than three years, food insecurity has been associated with poor infant health, and the likelihood of hospitalization.
The Children's Sentinel Nutritional Assessment Program (C-SNAP) interviewed caregivers from low-income households with children aged four to 36 months at five pediatric clinic/emergency department sites in Boston, Little Rock, Baltimore, Minneapolis and Philadelphia. The target child from each household was weighed and weight-for-age score was calculated.
In the sample of 2,010 families, the researchers found 21 percent reported food insecurity. The results of the analyses revealed that children from food-insecure households, compared with those from food-secure households, were two thirds more likely to experience developmental risks. Household food insecurity, (with or without the report of family hunger), even in the presence of appropriate weight-for age, is an important risk factor for the health, development and behavior of children less than three years of age.
According to the researchers the clinical and public policy implications of this study are striking. "Providing nutritional and developmental interventions to young children and their families is a proactive step that might decrease the need for later, more extensive interventions for developmentally or behaviorally impaired children of school age," said lead author Ruth Rose-Jacobs, ScD, an assistant professor of pediatrics at BUSM and a research scientist at BMC.
"Interventions for food insecurity and developmental risk are available and overall have been successful. Linking families to the Food Stamp Program and/or the Supplemental Nutrition Program for Women, Infants and Children is an important intervention that should be recommended if indicated by risk surveillance or developmental screening," she adds.
This study appears in the January 2008 issue of the journal Pediatrics.
Adapted from materials provided by Boston University
A skull the size of a car? Subcompact or full size?
Giant rat that once roamed the earth
The fossilised skull of a rat the size of a car has been unearthed. The creature lived about four million years ago, weighed about a tonne and ate mostly soft vegetation. It was so big that it probably spent much of its life semi-submerged in water, like a hippo, to reduce the stresses caused by its size.
Palaeontologists found the skull in rock deposits in Uruguay. It is believed to date back two to four million years to a time when giant wildlife was commonplace in South America.
The rodent, Josephoartigasia monesi, was uncovered by Andrés Rinderknecht and Ernesto Blanco. It has been nicknamed Mighty Mouse and is thought to have been similar to the capybara and pacarana, much smaller creatures that are still found in South America. Capybaras are the biggest living rodents at just over 60kg fully grown, while pacaranas weigh 15kg. The common rat weighs about 300g.
J. monesi is thought to have weighed about a tonne and the biggest specimens could have been more than 2.5 tonnes — about the same as hippopotamuses, which range from 1.4 tonnes to 3.2 tonnes.
The rodent was estimated to be about 3m (10 feet) long and 1.5m tall. Its huge incisors were more than 30cm (12in) long, of which 10cm would have been exposed.
The incisors puzzled the researchers because they were much tougher than necessary for an animal that ate only soft plants. Dr Blanco suggested that they could have been used to fell trees like beavers do, or to fight off predators or courtship rivals.
“It probably ate aquatic plants and fruits, and the environment probably was a forest near fresh water,” Dr Blanco said. “But much work is needed to have a definitive picture. We are working on biomechanical determination of the bite force to better understand this point.”
It shared the Earth with sabre-tooth cats and giant predatory birds that did not fly but could run down prey at terrifying speeds. Its great bulk would have protected it from the killer birds, but its young would have been at risk.
The near-complete skull delighted palaeontologists studying giant South American rodents. Before, they had been limited to bone fragments.
Other teeth in the skull were too small to have allowed the animal to have chewed food well. Researchers concluded that it must have consumed soft vegetation, including fruit.
Rodents make up about 40 per cent of all mammals but the new South American species was still about twice the size of the next biggest, a South American species called Phoberomys.
The skull came from a type of rodent, known as dinomyids, that include today’s pacaranas and which during the Miocene and Pliocene periods, from about 2 to 23 million years ago, underwent an evolutionary explosion creating many species in modern-day Argentina, Brazil, Uruguay, Venezuela, Bolivia and Colombia.
Dr Rinderknecht, of the National Museum of Natural History and Anthropology in Montevideo, the Uruguayan capital, and Dr Blanco, of the Institute of Physics in Montevideo, reported their findings in the journal Proceedings of the Royal Society B.
Because we can, that’s why. The benefit? Because we can.
Mice Given Bat-like Forelimbs Through Gene Switch
ScienceDaily (Jan. 16, 2008) — A research team led by Dr. Richard Behringer at MD Anderson Cancer Center reports that they have successfully switched the mouse Prx1 gene regulatory element with the Prx1 gene regulatory region from a bat -- and although these two species are separated by millions of years of evolution -- the resulting transgenic mice displayed abnormally long forelimbs.
While forelimb length is just one of several key morphological changes that occurred during the evolution of the bat wing, this unprecedented finding demonstrates that evolution can be driven by changes in the patterns of gene expression, rather than solely by changes in the genes, themselves.
Prx1 is a paired-box homeodomain transcription factor, with an established role in limb bone growth. Dr. Behringer and colleagues identified a conserved Prx1 enhancer domain, which regulates expression of Prx1 in the developing forelimb.
To study the evolutionary contribution of the Prx1 enhancer to the morphological differences between the bat and mouse forelimb, Dr. Behringer and colleagues replaced the endogenous mouse Prx1 enhancer with that of the bat. The transgenic mice showed higher expression levels of Prx1 in the perichondrium, increased chondrocyte proliferation, and ultimately, longer forelimbs.
Dr. Behringer describes the significance of his finding as such: "Darwin suggested that "successive slight modifications" would ultimately result in the evolution of diverse limb morphologies, like a hand, wing, or fin. The genetic change we engineered in mice may be one of those "slight modifications" to evolve a mammalian wing."
This research was published In the January 15th issue of Genes and Development.
Adapted from materials provided by Cold Spring Harbor Laboratory, via EurekAlert!, a service of AAAS.
By teasing these mice, we were able to show that humans get off on the thug tip.
Aggression As Rewarding As Sex, Food And Drugs, New Research Shows
ScienceDaily (Jan. 15, 2008) — New research from Vanderbilt University shows for the first time that the brain processes aggression as a reward - much like sex, food and drugs - offering insights into our propensity to fight and our fascination with violent sports like boxing and football.
“Aggression occurs among virtually all vertebrates and is necessary to get and keep important resources such as mates, territory and food,” Craig Kennedy, professor of special education and pediatrics, said. “We have found that the ‘reward pathway’ in the brain becomes engaged in response to an aggressive event and that dopamine is involved.”
“It is well known that dopamine is produced in response to rewarding stimuli such as food, sex and drugs of abuse,” Maria Couppis, who conducted the study as her doctoral thesis at Vanderbilt, said. “What we have now found is that it also serves as positive reinforcement for aggression.”
For the experiments, a pair of mice - one male, one female - was kept in one cage and five “intruder” mice were kept in a separate cage. The female mouse was temporarily removed, and an intruder mouse was introduced in its place, triggering an aggressive response by the “home” male mouse. Aggressive behavior included tail rattle, an aggressive sideways stance, boxing and biting.
The home mouse was then trained to poke a target with its nose to get the intruder to return, at which point it again behaved aggressively toward it. The home mouse consistently poked the trigger, which was presented once a day, indicating it experienced the aggressive encounter with the intruder as a reward.
The same home mice were then treated with a drug that suppressed their dopamine receptors. After this treatment, they decreased the frequency with which they instigated the intruder’s entry.
In a separate experiment, the mice were treated with the dopamine receptor suppressors again and their movements in an open cage were observed. They showed no significant changes in overall movement compared to times when they had not received the drugs. This was done to demonstrate that their decreased aggression in the previous experiment was not caused by overall lethargy in response to the drug, a problem that had confounded previous experiments.
The Vanderbilt experiments are the first to demonstrate a link between behavior and the activity of dopamine receptors in response to an aggressive event.
“We learned from these experiments that an individual will intentionally seek out an aggressive encounter solely because they experience a rewarding sensation from it,” Kennedy said. “This shows for the first time that aggression, on its own, is motivating, and that the well-known positive reinforcer dopamine plays a critical role.”
Kennedy is chair of Vanderbilt’s Peabody College of education and human development’s special education department, which is consistently ranked as the top special education program in the nation. He is also director of the Vanderbilt Kennedy Center for Research of Human Development’s Behavior Analysis Clinic.
Couppis conducted her research in affiliation with the Vanderbilt Brain Institute. She is also affiliated with the Vanderbilt Kennedy Center for Research on Human Development and the Vanderbilt Center for Integrative and Cognitive Neuroscience.
The research will be published online the week of Jan. 14 by the journal Psychopharmacology.
The research was supported by a Discovery Grant from Vanderbilt University.
Peeping tom checks out God’s cupboard. Find sugar, salt and lard.
Life's Ingredients Detected In Far Off Galaxy
ScienceDaily (Jan. 15, 2008) — Astronomers from Arecibo Observatory radio telescope in Arecibo, Puerto Rico, have detected for the first time the molecules methanimine and hydrogen cyanide -- two ingredients that build life-forming amino acids -- in a galaxy some 250 million light years away.
When combined with water, the molecules form glycene, the simplest amino acid and a building block of life on Earth.
The Arecibo astronomers focused on the distant galaxy Arp 220, an ultra-luminous starburst galaxy, because it forms new stars at a very high rate. They used the 305-meter, or 1,000-foot diameter, Arecibo radio telescope, the world's largest and most sensitive, to observe the galaxy at different frequencies. The observations, made in April 2007, were the first use of the 800 megahertz wide-band mode of the telescope's main spectrometer.
The molecules were found by searching for radio emission at specific frequencies. Each chemical substance has its own unique radio frequency, much like people have unique fingerprints.
"We weren't targeting any particular molecule, so we didn't know what we were going to find -- we just started searching, and what we found was incredibly exciting," said Tapasi Ghosh, an Arecibo astronomer.
"The fact that we can observe these substances at such a vast distance means that there are huge amounts of them in Arp 220," said Emmanuel Momjian, a former Arecibo astronomer, now at the National Radio Astronomy Observatory in Socorro, N.M. "It is indeed very intriguing to find that the ingredients of life appear in large quantities where new stars and planets are born."
The astronomy team, led by Arecibo astronomer Christopher Salter, announced the discovery Jan. 11 in a poster presented at the American Astronomical Society meeting in Austin, Texas. In addition to Salter, Momjian and Ghosh, the other researchers included Arecibo astronomers Robert Minchin and Mikael Lerner; Barbara Catinella, a former Arecibo astronomer now at the Max Plank Institute for Astrophysics in Germany; and Mayra Lebron, a former Arecibo astronomer now at the University of Puerto Rico.
The Arecibo Observatory is part of the National Astronomy and Ionosphere Center, a national research center operated by Cornell for the National Science Foundation.
Adapted from materials provided by Cornell University.
Keeping mice regular
Probiotics in yogurt affect metabolism
LONDON, Jan. 16 (UPI) -- Probiotics, found in yogurt containing live bacteria, have a tangible effect on the metabolism, researchers in Britain and Switzerland found.
Researchers from Imperial College London and Nestle Research Center, in Lausanne, Switzerland, gave two different types of probiotic drink to mice that had been transplanted with human microbes found in the intestine.
The scientists compared the levels of different metabolites in the liver, blood, urine and feces, of mice who had received treatment with probiotics and those that had not.
The study, published in the journal Molecular Systems Biology, found treatment with probiotics had a whole range of biochemical effects, and that these effects differed markedly between the two probiotic strains -- Lactobacillus paracasei and Lactobacillus rhamnosus.
One of the many biochemical changes observed by the researchers was a change in how mice treated with probiotics metabolized bile acids that emulsify fats in the upper gut.
If probiotics can influence the way in which bile acids are metabolized they may change how much fat the body is able to absorb, the study said.
Study shows that just being in the world can make humans depressed. Pill companies cheer.
Nature And Nurture Are Both To Blame For Depression, Study Says
ScienceDaily (Jan. 16, 2008) — Depression is one of the most common forms of psychopathology. According to diathesis' stress theories of depression, genetic liability interacts with negative life experiences to cause depression.
Traditionally, most studies testing these theories have focused on only one component of the diathesis' stress model: either genetics or environment, but not their interaction. However, because of recent advances in genetics and genomics, researchers have begun using a new design that allows them to test the interaction of genetic and environmental liabilities -- the G x E design.
Studies suggest that the neurotransmitter dopamine may play a role in the risk for depression. Early negative interpersonal environments (i.e. rejecting parents) have also been implicated. So, University of Notre Dame psychologist, Gerald Haeffel, and colleagues investigated whether a gene associated with dopamine interacted with maternal parenting style to predict episodes of depression.
The researchers studied 177 male adolescents from a juvenile detention center in Russia. These participants were ideal candidates for the study because depression rates rise so dramatically during this period in life. The researchers used a structured diagnostic interview to diagnose depression and a questionnaire to assess aspects of maternal parental rearing (i.e. physical punishment, hostility, lack of respect for the child’s point of view, and unjustified criticism in front of others).
The results are fascinating. While neither factor alone predicted depression, the boys with especially rejecting mothers, and a specific form of the dopamine transporter gene were at higher risk for major depression and suicidal ideation. This study, which appears in the January issue of Psychological Science, a journal of the Association for Psychological Science, is among the first to support the role of a dopamine related gene in the onset of depression.
By the year 2020, depression is projected to be the 2nd leading cause of disability worldwide. Identifying factors that contribute to risk and resilience for depression is vital to our society. The results suggest that using psychosocial interventions to increase dopamine activity in the brain, helping patients focus on identifying and pursuing new goals and rewards could prove beneficial to lowering depression rates.
Adapted from materials provided by Association for Psychological Science.
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