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Spanking, Hitting Kids in Public Surprisingly Common, Study Finds

Stephanie Pappas
LiveScience
Fri, 03 Aug 2012 13:10 UTC
Crying Child
© Christophe Testi, ShutterstockA new study published in the journal Behavior and Social Issues finds that kids spank and otherwise physically discipline their children in public quite frequently.
Parents get physical with unruly children far more in public than they do when they know psychologists or other researchers are looking, a new study finds.

In an experiment that involved surreptitiously watching parents discipline their kids in public places such as restaurants, researchers found that in 23 percent of cases, mom or dad resorted to "negative touch" to get their child to comply. Negative touch can include anything from restraining and spanking to pinching and hitting.

The findings suggest that most social science research in parenting misses out on these sorts of incidents, study researcher Kathy Stansbury, a professor of human development and family studies at Michigan State University, said in a statement.

"I have also seen hundreds of kids and their parents in a lab setting, and never once witnessed any of this behavior," Stansbury said.
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Meteor

"The Returns of Comets are much more frequent than is vulgarly reckoned", or "How I Discovered Halley's Comet", by Edmond Halley

Rebecca J. Rosen
The Atlantic
Fri, 03 Aug 2012 13:21 UTC
Image
© Wikimedia Commons
"Hence, we may justly conclude that the Returns of Comets are much more frequent than is vulgarly reckoned."

There is something truly thrilling about the first-hand accounts of scientists who have homed in on an idea or a fact that is now common knowledge. A few artifacts of such moments -- Darwin's early tree-of-life sketches or the first few minutes of this BBC documentary on Andrew Wiles' work on Fermat's Last Theorem -- convey the emotions and the creativity that surround those discoveries. A paper, published in Philosophical Transactions Vol. 30 (1717-1719) relaying the details of the discovery of a comet as "seen at London on the 10th of June 1717" and now available on JSTOR, does much the same.

Edmond Halley described the events as such:
On Monday, June 10, in the Evening, the Sky being very serene and calm, I was desirous to take a view of the disk of Mars (then very near the Earth, and appearing very glorious) to see if I could distinguish in my 24 Foot Telescope, the Spots said to be seen on him. Directing my Tube for the purpose, I accidentally fell upon a small whitish Appearance near the Planet, resembling in all respects such a Nebula ... The Reverend Mr. Miles Williams, Mr. Alban Thomas, and myself contemplated this Appearance for above an Hour ... and we could not be deceiv'd as to its Reality; but the slowness of its Motion made us at that time conclude that it had none, and that it was rather a Nebula than a Comet.

Comment: Reign of Fire: Meteorites, Wildfires, Planetary Chaos and the Sixth Extinction
Meteorites, Asteroids, and Comets: Damages, Disasters, Injuries, Deaths, and Very Close Calls
Impact Hazards on a Populated Earth?
Tunguska, the Horns of the Moon and Evolution

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Beaker

New type of double-stranded DNA structure discovered


Source
Fri, 03 Aug 2012 11:53 UTC
novel double-stranded DNA structure
© National University of SingaporeThis novel double-stranded DNA structure produced through mechanical stretching has been successfully demonstrated by researchers from the National University of Singapore.
By way of mechanical stretching, National University of Singapore researchers identify a novel double-stranded DNA structure, thus successfully resolving a 16-year-old scientific debate over the existence of a double-stranded DNA structure.

Double-stranded DNA has often been described as a right-handed helical structure, known as B-DNA. To perform its multiple functions, double-stranded DNA has multiple structures depending on conditions. For example, the melted DNA bubble forms during transcription elongation and the left-handed helical Z-DNA forms hypothetically during transcriptional regulations.

Scientists have been proposing a novel form of double-stranded DNA structure since 1996. Referred to as 'S-DNA', it is produced from stretching the B-form DNA beyond a certain 'transition force' of around 65 pN to approximately 1.7-fold in length (termed as DNA overstretching transition). Its existence has sparked a 16-year scientific debate since it was proposed, as many other evidences suggested that DNA overstretching transition was merely a force-induced DNA melting transition, leading to peeled-apart single-stranded DNA.

At National University of Singapore (NUS), the research was led by Associate Professor Jie Yan, from the Department of Physics, Faculty of Science and Mechanobiology Institute, Singapore. It succeeded in demonstrating the intricacies of the DNA mechanics in highly sensitive single-DNA stretching experiments.
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Blackbox

Scientists probe link between magnetic polarity reversal and mantle processes


Terra Daily / SPX
Fri, 03 Aug 2012 09:37 UTC
Image
© Unknown
Scientists at the University of Liverpool have discovered that variations in the long-term reversal rate of the Earth's magnetic field may be caused by changes in heat flow from the Earth's core into the base of the overlying mantle.

The Earth is made up of a solid inner core, surrounded by a liquid outer core, in turn covered by a thicker or more viscous mantle, and ultimately by the solid crust beneath our feet.

The magnetic field is generated by the motions of the liquid iron alloy in the outer core, approximately 3,000 km beneath the Earth's crust. These motions occur because the core is losing heat to the overlying solid mantle that extends up to the crust on which we live.
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Telescope

Looking for extraterrestrial 'bubbles' in neighboring galaxies

George Dvorsky
io9
Wed, 01 Aug 2012 09:23 UTC
spiral galaxy
© Unknown
There's been an exciting shift in scientific thinking about life beyond Earth recently. Extraterrestrial-seeking group SETI has started to recognize the importance of detecting alien artifacts along with radio signals. The most viable target for these searches is the Dyson sphere, a massive shell that envelops an entire star. But as Discovery's Ray Villard rightly points out, the difficulty of finding these near-invisible objects could be offset by searching for them in nearby galaxies where their presence would be much more obvious.

Finding a Dyson sphere is not easy - and it's not because we don't know how to do it. As we've discussed before, the trick is to distinguish the infrared signature of a Dyson sphere candidate from natural phenomenon. According to Villard, Dyson hunters have catalogued 17 "quasi-plausible" signatures - but they can't prove one way or another that they're not just, say, stars enshrouded in dust.

Consequently, it will be very difficult to prove that a Dyson sphere exists - at least one that's nearby.
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Robot

World's First Real-Sized, Five-Fingered Robotic Hand Able to Grasp and Manipulate Objects


Agence France-Presse
Thu, 02 Aug 2012 00:00 UTC
European researchers said Thursday they had developed the world's first real-sized, five-fingered robotic hand able to grasp and manipulate objects with human-like dexterity.
Image
© unknownRobotics student Gildo Andreoni works on a Dexmart robotic hand built at the University of Bologna. Dexmart's hands are 'smart' enough to make cups of coffee and pick up clothes from the floor
Getting robots to manoeuvre objects with precision has posed many problems for engineers in their quest to build humanoid machines to serve as domestic aides, emergency rescuers or factory workers.

Industrial robotic "grippers" already exist that are able to grasp objects and move them but are unable to handle items as a human hand would -- grasping an egg without breaking it but also lifting heavy, bulky things.

It has also proved difficult to size prototypes on human measurements.

The team from Italy and Germany built a hand using strings that are twisted by small, high-speed motors in five fingers, each with three segments.
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Blackbox

Full Moon - How Does It Happen? How Does It Affect Us?


SPACE.com
Thu, 02 Aug 2012 21:03 UTC
What happens when the Sun Earth and Moon line up (in that order)? Do people (or animals) get crazy? Commit more crimes? The Moon always shows us the same face, but there's only one instant when the Moon is truly "Full." @DavidSkyBrody explains.

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Igloo

New Evidence Points To Tropical Times For Antarctic During Eocene Epoch

Brett Smith
RedOrbit
Thu, 02 Aug 2012 15:15 UTC
Ice Cave
© Photos.com
As the world's greatest athletes compete for gold, silver, and bronze in London, new scientific evidence suggests that future summer Olympics could be hosted in a more remote location: Antarctica.

An international team of climate scientists has discovered 50 million-year-old fossilized pollen in the seabed off the eastern coast of the polar continent, according to their report published this week in the journal Nature.

The discovery opened a window into the climate of the Eocene epoch, when temperatures around Antarctica were between 65 and 70 degrees Fahrenheit in the summer months and atmospheric carbon dioxide levels were over twice as high as today. Scientists said the Antarctic winters would have had extended periods of darkness like today, but with much warmer temperatures.

Although the polar temperatures were much higher during the Eocene, evidence points to a temperature gradient from pole to equator that was much smaller than modern times.

According to the study, this latest discovery could also give us a glimpse into future Earth climates if atmospheric greenhouse gas concentrations were to continue to rise.

"Recently the early Eocene has received considerable interest because it may provide insight into the response of Earth's climate and biosphere to the high atmospheric carbon dioxide levels that are expected in the near future as a consequence of unabated anthropogenic carbon emissions," the authors wrote.
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Info

Mom's Genes May Explain Why Women Outlive Men

Stephanie Pappas
LiveScience
Thu, 02 Aug 2012 11:00 UTC
mtDNA
© Wire_man/ShutterstockThe mitochondria are the energy-generating organelles in the cell.
An evolutionary "loophole" might explain why males of many species live shorter lives than their female counterparts, a new study finds.

The loophole lies in the mitochondria, the energy-generating parts of our cells. The mitochondria have their own DNA, separate from the DNA that resides in the nucleus of the cell that we usually think of when we think of the genome. In almost all species, the mitochondria DNA is passed down solely from mother to child, without input from dad.

This direct line of inheritance may allow harmful mutations to accumulate, according to a new study detailed today (Aug. 2) in the journal Current Biology. Ordinarily, natural selection helps keep harmful mutations to a minimum by ensuring they're not passed down to offspring. But if a mitochondrial DNA mutation is dangerous only to males and doesn't harm females, there's nothing to stop mom from passing it to her daughters and sons.

"If a mitochondrial mutation pops up that is benign in females, or a mutation pops up that is beneficial to females, this mutation will slip through the gates of natural selection and go through to the next generation," said study researcher Damian Dowling, an evolutionary biologist at Monash Univeristy in Australia.

The result: a load of mutations that don't harm females, but add up to a shorter life span for males.
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Info

Secret to Elephants' Thundering Calls Discovered

Stephanie Pappas
LiveScience
Thu, 02 Aug 2012 13:00 UTC
Elephant
© Angela StoegerAfrican elephants in Amboseli National Park in Kenya.
Elephants' deepest calls can thunder up to 6 miles (10 kilometers) away. Now, researchers have learned for the first time how the massive animals produce these sounds.

It turns out that they do it in the same way that humans talk, pushing air through their vocal cords to make them vibrate. Elephants can go much lower than humans, however, because their vocal cords are eight times longer.

"The sounds the elephants make are off the piano keyboard," said study researcher Christian Herbst, a voice scientist at the University of Vienna, Austria. In fact, at less than 20 hertz in frequency, the main components of these ultra-deep calls aren't detectable to the human ear.

Until now, researchers weren't sure how elephants produced such low sounds. In fact, it's difficult to study voice production in animals in general, Herbst told LiveScience. In humans, researchers can insert cameras through the throat into the larynx, or voicebox, while people make different sounds. Animals tend to be less cooperative on that front, Herbst said.

There are two ways to produce sound by vibrating the vocal cords (or vocal folds, as scientists call them). The first is called active muscular contraction, or AMC. With this method, the throat muscles actively contract to vibrate the vocal folds. AMC is how cats purr.

The other method of sound production is called the myoelastic-aerodynamic (MEAD) mode. The MEAD mode uses air from the lungs to vibrate the vocal folds. MEAD is how humans talk and sing.
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