Headlines of the day
Should zoo let polar bear eat her cubs? (cnn)
Wiretaps Cut Because FBI Didn't Pay Phone Bill (WCBS)
"What are you doing here?": man asks wife at brothel
You know, some like garlic and some like to dance
Chimpanzees May Build Their 'Cultures' In A Similar Way To Humans
ScienceDaily (Jan. 10, 2008) — Socially-learned cultural behaviour thought to be unique to humans is also found among chimpanzees colonies, scientists at the University of Liverpool have found.
See also:
Historically, scientists believed that behavioural differences between colonies of chimpanzees were due to variations in genetics. A team at Liverpool, however, has now discovered that variations in behaviour are down to chimpanzees migrating to other colonies, proving that they build their 'cultures' in a similar way to humans.
Primatologist, Dr Stephen Lycett, explains: "We knew there were behavioural differences between chimpanzee colonies, but nobody really knew why. It was assumed that young chimpanzees developed certain behavioural characteristics from the genes passed down from their parents, but there was no evidence to clearly support this. It was also thought that because behaviour was dictated by biology, chimpanzees did not have a 'culture' in the same way that humans do."
By looking at how chimpanzees prepare their food, the research team discovered that one colony used stone tools to crack nuts, whereas another colony used wooden tools as well as stone. They found these methods of preparing food have spread 4000km from East to West Africa over the more than 100,000 years. The team also found this true of other techniques, such as grooming. The research suggests that behavioural variety is due to how chimpanzees socialise rather than genetics as previously thought.
To investigate the theory further researchers built an evolutionary tree of chimpanzee behaviour in East and West Africa as well as a genetic family tree. They had expected to find that those with similar genetic patterns also shared behavioural similarities. Instead, they found that some chimpanzees shared behavioural similarities with those that were genetically different from them.
Dr Lycett, added: "This explains why some colonies, for example, use similar methods for finding food, adopting certain behaviour and adapting different methods to suit their own environment. In this sense we can see for the first time that culture exists in our closest relatives."
Sounds like a job for Dog the Bounty Hunter
Galaxy May Hold Hundreds Of Rogue Black Holes
ScienceDaily (Jan. 10, 2008) — If the latest simulation of what happens when black holes merge is correct, there could be hundreds of rogue black holes, each weighing several thousand times the mass of the sun, roaming around the Milky Way galaxy.
"Rogue black holes like this would be very difficult to spot," says Vanderbilt astronomer Kelly Holley-Bockelmann, who is presenting the results of the supercomputer simulation at a meeting of the American Astronomical Society on Jan. 9 in Austin, Texas. Much of the research was done at Penn State University in collaboration with Deirdre Shoemaker and Nicolas Yunes before Holley-Bockelmann moved to Vanderbilt. Kayhan Gultekin at the University of Michigan also participated in the study.
"Unless it's swallowing a lot of gas, about the only way to detect the approach of such a black hole would be to observe the way in which its super-strength gravitational field bends the light that passes nearby. This produces an effect called gravitational lensing that would make background stars appear to shift and brighten momentarily," she says.
The research focused on modeling "intermediate mass" black holes, whose very existence is controversial. Astronomers have ample evidence that small black holes less than 100 solar masses are produced when giant stars explode. There is similar evidence that "super-massive" black holes weighing the equivalent of millions to billions of solar masses sit at the heart of many galaxies, including the Milky Way. In addition, theoreticians have predicted that globular clusters -- ancient, gravitationally bound groups of 100,000 to a million stars -- should contain a third class of black holes, called intermediate mass black holes, that weigh a few thousand solar masses. But so far there have only been two tentative observations of objects of this sort.
In the past two years, scientists have succeeded in numerically simulating black hole mergers that incorporate Einstein's theory of relativity. One of the big surprises to come from this effort is the prediction that when two black holes that are rotating at different speeds or are different sizes combine, the newly merged black hole receives a big kick due to conservation of momentum, pushing it away in an arbitrary direction at velocities as high as 4,000 kilometers per second.
"This is much higher than anyone predicted. Even the average kick velocity of 200 kilometers per second is extremely high when compared to the escape velocities of typical astronomical objects," says Holley-Bockelmann. "We realized that basically any black hole merger would kick the new remnant out of a globular cluster, because the escape velocity is less than 100 kilometers per second."
Using the facilities of Vanderbilt's Advanced Center for Computation, Research and Education, Holley-Bockelmann's team ran a number of simulations of the growth of intermediate mass black holes as they combine with a number of stellar-sized black holes, which are plentiful in globular clusters, paying close attention to the kick they received after each merger.
"We used different assumptions for the initial black hole mass, for the range of stellar black hole masses within a globular cluster, and assumed that the spins and spin orientations were distributed randomly. With our most conservative assumptions, we found that, even if every globular cluster started out with an intermediate-sized black hole, only about 30 percent retain them through the merger epoch. With our least conservative assumptions, less than 2 percent of the globular clusters should contain intermediate mass black holes today," she says.
If the roughly 200 globular clusters in the Milky Way have indeed spawned intermediate-sized black holes, this means that hundreds of them are probably wandering invisibly around the Milky Way, waiting to engulf the nebulae, stars and planets that are unfortunate enough to cross their paths.
Fortunately, the existence of a few rogue black holes in the neighborhood does not present a major danger. "These rogue black holes are extremely unlikely to do any damage to us in the lifetime of the universe," Holley-Bockelmann stresses. "Their danger zone, the Schwarzschild radius, is really tiny, only a few hundred kilometers. There are far more dangerous things in our neighborhood!"
The other 40 percent feels the same way. They just don’t want to talk about it.
60 Percent Of Psychotherapy Clients Felt Therapy Didn't End On Time
ScienceDaily (Jan. 10, 2008) — Sixty percent of private practice dynamically oriented psychotherapy clients felt that their therapy either lasted too long or ended too soon, according to recent research conducted by Prof. David Roe, Head of the Department of Community Mental Health, Faculty of Social Welfare and Health Sciences at the University of Haifa. "While there is widespread agreement that an ideal termination of psychotherapy occurs naturally, with an agreement of the timing between therapist and client, our research reveals that more often than not -- this does not happen" said Prof. Roe.
In the study, which was conducted in collaboration with Dr. Rachel Dekel and Galit Harel from Bar Ilan University and Prof. Shmuel Fennig of Tel Aviv University Medical School, 82 people who were in private practice psychodynamically oriented psychotherapy for at least 6 months (and average of 2 years), which had recently ended, were assessed regarding the way they experienced the timing of, reasons for and feelings about their psychotherapy termination.
The findings, which were recently published in three psychotherapy journals: "Bulletin of the Menninger Clinic"; "The Journal of the American Academy of Psychoanalysis & Dynamic Psychiatry" and "Psychology and psychotherapy: Theory, research and practice", revealed that 84% of participants stated that they initiated the termination; the remaining 16% stated that termination was either by mutual agreement or initiated by the therapists.
The results of the study show that only 40% of the clients felt that the therapy ended at the appropriate time, 37% felt that it ended earlier than it should have and 23% felt that the therapy went on for too long.
The most frequent reasons for termination among those who experienced it as too early were financial constrains (34.5%) and mismatch with therapist (27.6%). Among those clients who experienced therapy as lasting too long, the most frequent reasons were: feeling uncomfortable toward the therapist (26.3%), hope that the treatment would improve (21.1%) and dependence on the therapist (21.1%).
In general, clients who reported that termination was on time were more satisfied with their therapy. Factors contributing to positive feelings about termination included perceiving the experience of termination as an expression of independence, reflection of positive aspects of the therapeutic relationship and a reflection of positive gains experienced in therapy.
"Whereas clinical lore has consistently suggested that therapists must help clients focus on the emotionally painful aspects of this period and the difficulty in separating, the emerging data suggest that it is equally important to relate to the clients' positive feelings" said Professor Roe, "Results suggest that clients find terminating psychotherapy at the right time important and yet difficult to achieve, and that clients experience a wide range of feelings, many positive, during the termination phase, which call for a reconceptualization of the role of the therapist during this important phase of psychotherapy."
If you keep flushing that stuff, it’s got to end up somewhere
Surprise found in Earth’s plumbing system (MSNBC)
Seismologists have used tiny earthquakes to make the first images of the inside of a deep sea vent — and it doesn’t look like anyone thought it would.
Sea floor vents (often called "black smokers" because of the cloud of chemicals they ooze) are the outflow channels of vast plumbing systems that exist under the Earth's mid-ocean ridges, which run across some 37,000 miles (60,000 kilometers) of the seafloor.
Hydrothermal vents are found all over the globe.
Story continues below ↓advertisement
The hypothetical image scientists had drawn of these vent systems had cold, deep-ocean water being forced down by overlying pressure through large faults along the ridges. The water was then thought to be superheated by shallow volcanism, eventually rising toward the middle of the ridges where the vents tend to be clustered.
But the new images, detailed in a study in the Jan. 10 issue of the journal Nature, paint a different picture: Ocean water appears to descend through tiny cracks in the ridge, instead of large faults, then runs below the ridge along its axis in a tunnel-like zone just above a magma chamber for several kilometers. As the water gets heated, it rises back to the sea floor (like a pot of boiling water) and bubbles out through a series of vents.
"If you google on images of hydrothermal vents, you come up with cartoons that don't at all match what we see," said lead study author Maya Tolstoy of the Lamont-Doherty Earth Observatory, a part of Columbia University.
The new images of the vent system, taken along the East Pacific Rise about 565 miles southwest of Acapulco, Mexico, were created using seismometers that recorded 7,000 tiny, shallow earthquakes over the course of seven months in 2003 and 2004.
The quakes are thought to be the result of cold water passing through the hot rocks below the surface and picking up their heat, causing the rocks to cool and shrink, and therefore crack and create small tremors.
The new model also suggests that the water moves a lot faster than previously thought — perhaps a billion gallons per year flows through the particular system studied.
The findings could help scientists determine how the thriving communities around these vents travel along seafloor currents and how the nutrients that feed them flow.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment