Nanodiamonds are forever: Did comet collision leave layer of nanodiamonds across Earth?

Date:

August 27, 2014

Source:

University of California - Santa Barbara

Summary:

A comet collision with Earth caused abrupt environmental stress and degradation that contributed to the extinction of most large animal species then inhabiting the Americas, a group of scientists suggests. The catastrophic impact and the subsequent climate change also led to the disappearance of the prehistoric Clovis culture, and to human population decline. Now focus has turned to the character and distribution of nanodiamonds, one type of material produced during such an extraterrestrial collision. The researchers found an abundance of these tiny diamonds distributed over 50 million square kilometers across the Northern Hemisphere.

Most of North America's megafauna -- mastodons, short-faced bears, giant ground sloths, saber-toothed cats and American camels and horses -- disappeared close to 13,000 years ago at the end of the Pleistocene period. The cause of this massive extinction has long been debated by scientists who, until recently, could only speculate as to why.

A group of scientists, including UC Santa Barbara's James Kennett, professor emeritus in the Department of Earth Science, posited that a comet collision with Earth played a major role in the extinction. Their hypothesis suggests that a cosmic-impact event precipitated the Younger Dryas period of global cooling close to 12,800 years ago. This cosmic impact caused abrupt environmental stress and degradation that contributed to the extinction of most large animal species then inhabiting the Americas. According to Kennett, the catastrophic impact and the subsequent climate change also led to the disappearance of the prehistoric Clovis culture, known for its big game hunting, and to human population decline.

In a new study published this week in the Journal of Geology, Kennett and an international group of scientists have focused on the character and distribution of nanodiamonds, one type of material produced during such an extraterrestrial collision. The researchers found an abundance of these tiny diamonds distributed over 50 million square kilometers across the Northern Hemisphere at the Younger Dryas boundary (YDB). This thin, carbon-rich layer is often visible as a thin black line a few meters below the surface.

Kennett and investigators from 21 universities in six countries investigated nanodiamonds at 32 sites in 11 countries across North America, Europe and the Middle East. Two of the sites are just across the Santa Barbara Channel from UCSB: one at Arlington Canyon on Santa Rosa Island, the other at Daisy Cave on San Miguel Island.

"We conclusively have identified a thin layer over three continents, particularly in North America and Western Europe, that contain a rich assemblage of nanodiamonds, the production of which can be explained only by cosmic impact," Kennett said. "We have also found YDB glassy and metallic materials formed at temperatures in excess of 2200 degrees Celsius, which could not have resulted from wildfires, volcanism or meteoritic flux, but only from cosmic impact."

The team found that the YDB layer also contained larger than normal amounts of cosmic impact spherules, high-temperature melt-glass, grapelike soot clusters, charcoal, carbon spherules, osmium, platinum and other materials. But in this paper the researchers focused their multi-analytical approach exclusively on nanodiamonds, which were found in several forms, including cubic (the form of diamonds used in jewelry) and hexagonal crystals.

"Different types of diamonds are found in the YDB assemblages because they are produced as a result of large variations in temperature, pressure and oxygen levels associated with the chaos of an impact," Kennett explained. "These are exotic conditions that came together to produce the diamonds from terrestrial carbon; the diamonds did not arrive with the incoming meteorite or comet."

Based on multiple analytical procedures, the researchers determined that the majority of the materials in the YDB samples are nanodiamonds and not some other kinds of minerals. The analysis showed that the nanodiamonds consistently occur in the YDB layer over broad areas.

"There is no known limit to the YDB strewnfield which currently covers more than 10 percent of the planet, indicating that the YDB event was a major cosmic impact," Kennett said. "The nanodiamond datum recognized in this study gives scientists a snapshot of a moment in time called an isochron."

To date, scientists know of only two layers in which more than one identification of nanodiamonds has been found: the YDB 12,800 years ago and the well-known Cretaceous-Tertiary boundary 65 million years ago, which is marked by the mass extinction of the dinosaurs, ammonites and many other groups.

"The evidence we present settles the debate about the existence of abundant YDB nanodiamonds," Kennett said. "Our hypothesis challenges some existing paradigms within several disciplines, including impact dynamics, archaeology, paleontology and paleoceanography/paleoclimatology, all affected by this relatively recent cosmic impact."

Quantum physics enables revolutionary imaging method

Date:

August 28, 2014

Source:

University of Vienna

Summary:

Researchers have developed a fundamentally new quantum imaging technique with strikingly counter-intuitive features. For the first time, an image has been obtained without ever detecting the light that was used to illuminate the imaged object, while the light revealing the image never touches the imaged object.

A new quantum imaging technique generates images with photons that have never touched to object -- in this case a sketch of a cat. This alludes to the famous Schrödinger cat paradox, in which a cat inside a closed box is said to be simultaneously dead and alive as long there is no information outside the box to rule out one option over the other. Similarly, the new imaging technique relies on a lack of information regarding where the photons are created and which path they take.

Researchers from the Institute for Quantum Optics and Quantum Information (IQOQI), the Vienna Center for Quantum Science and Technology (VCQ), and the University of Vienna have developed a fundamentally new quantum imaging technique with strikingly counterintuitive features. For the first time, an image has been obtained without ever detecting the light that was used to illuminate the imaged object, while the light revealing the image never touches the imaged object.

In general, to obtain an image of an object one has to illuminate it with a light beam and use a camera to sense the light that is either scattered or transmitted through that object. The type of light used to shine onto the object depends on the properties that one would like to image. Unfortunately, in many practical situations the ideal type of light for the illumination of the object is one for which cameras do not exist.

The experiment published in Nature this week for the first time breaks this seemingly self-evident limitation. The object (e.g. the contour of a cat) is illuminated with light that remains undetected. Moreover, the light that forms an image of the cat on the camera never interacts with it. In order to realise their experiment, the scientists use so-called "entangled" pairs of photons. These pairs of photons -- which are like interlinked twins -- are created when a laser interacts with a non-linear crystal. In the experiment, the laser illuminates two separate crystals, creating one pair of twin photons (consisting of one infrared photon and a "sister" red photon) in either crystal. The object is placed in between the two crystals. The arrangement is such that if a photon pair is created in the first crystal, only the infrared photon passes through the imaged object. Its path then goes through the second crystal where it fully combines with any infrared photons that would be created there.

With this crucial step, there is now, in principle, no possibility to find out which crystal actually created the photon pair. Moreover, there is now no information in the infrared photon about the object. However, due to the quantum correlations of the entangled pairs the information about the object is now contained in the red photons -- although they never touched the object. Bringing together both paths of the red photons (from the first and the second crystal) creates bright and dark patterns, which form the exact image of the object.

Stunningly, all of the infrared photons (the only light that illuminated the object) are discarded; the picture is obtained by only detecting the red photons that never interacted with the object. The camera used in the experiment is even blind to the infrared photons that have interacted with the object. In fact, very low light infrared cameras are essentially unavailable on the commercial market. The researchers are confident that their new imaging concept is very versatile and could even enable imaging in the important mid-infrared region. It could find applications where low light imaging is crucial, in fields such as biological or medical imaging.

Mystery solved: 'Sailing stones' of Death Valley seen in action for the first time

Date:

August 28, 2014

Source:

Scripps Institution of Oceanography

Summary:

Racetrack Playa is home to an enduring Death Valley mystery. Littered across the surface of this dry lake, also called a "playa," are hundreds of rocks -- some weighing as much as 320 kilograms (700 pounds) -- that seem to have been dragged across the ground, leaving synchronized trails that can stretch for hundreds of meters.

Rarely formed sheets of ice push rocks across a dry lake in Death Valley. View from the ‘source hill’ on the south shore of Racetrack Playa. View is looking north on December 20, 2013 at 3:15 pm. Steady, light wind, 4–5 m/s has blown water to the northeast exposing newly formed rock trails.

Racetrack Playa is home to an enduring Death Valley mystery. Littered across the surface of this dry lake, also called a "playa," are hundreds of rocks -- some weighing as much as 320 kilograms (700 pounds) -- that seem to have been dragged across the ground, leaving synchronized trails that can stretch for hundreds of meters.

What powerful force could be moving them? Researchers have investigated this question since the 1940s, but no one has seen the process in action -- until now.

In a paper published in the journal PLOS ONE on Aug. 27, a team led by Scripps Institution of Oceanography, UC San Diego, paleobiologist Richard Norris reports on first-hand observations of the phenomenon.

Because the stones can sit for a decade or more without moving, the researchers did not originally expect to see motion in person. Instead, they decided to monitor the rocks remotely by installing a high-resolution weather station capable of measuring gusts to one-second intervals and fitting 15 rocks with custom-built, motion-activated GPS units. (The National Park Service would not let them use native rocks, so they brought in similar rocks from an outside source.) The experiment was set up in winter 2011 with permission of the Park Service. Then -- in what Ralph Lorenz of the Applied Physics Laboratory at the Johns Hopkins University, one of the paper's authors, suspected would be "the most boring experiment ever" -- they waited for something to happen.

But in December 2013, Norris and co-author and cousin Jim Norris arrived in Death Valley to discover that the playa was covered with a pond of water seven centimeters (three inches) deep. Shortly after, the rocks began moving.

"Science sometimes has an element of luck," Richard Norris said. "We expected to wait five or ten years without anything moving, but only two years into the project, we just happened to be there at the right time to see it happen in person."

Their observations show that moving the rocks requires a rare combination of events. First, the playa fills with water, which must be deep enough to form floating ice during cold winter nights but shallow enough to expose the rocks. As nighttime temperatures plummet, the pond freezes to form thin sheets of "windowpane" ice, which must be thin enough to move freely but thick enough to maintain strength. On sunny days, the ice begins to melt and break up into large floating panels, which light winds drive across the playa, pushing rocks in front of them and leaving trails in the soft mud below the surface.

"On Dec. 21, 2013, ice breakup happened just around noon, with popping and cracking sounds coming from all over the frozen pond surface," said Richard Norris. "I said to Jim, 'This is it!'"

These observations upended previous theories that had proposed hurricane-force winds, dust devils, slick algal films, or thick sheets of ice as likely contributors to rock motion. Instead, rocks moved under light winds of about 3-5 meters per second (10 miles per hour) and were driven by ice less than 3-5 millimeters (0.25 inches) thick, a measure too thin to grip large rocks and lift them off the playa, which several papers had proposed as a mechanism to reduce friction. Further, the rocks moved only a few inches per second (2-6 meters per minute), a speed that is almost imperceptible at a distance and without stationary reference points.

"It's possible that tourists have actually seen this happening without realizing it," said Jim Norris of the engineering firm Interwoof in Santa Barbara. "It is really tough to gauge that a rock is in motion if all the rocks around it are also moving."

Individual rocks remained in motion for anywhere from a few seconds to 16 minutes. In one event, the researchers observed rocks three football fields apart began moving simultaneously and traveled over 60 meters (200 feet) before stopping. Rocks often moved multiple times before reaching their final resting place. The researchers also observed rock-less trails formed by grounding ice panels -- features that the Park Service had previously suspected were the result of tourists stealing rocks.

"The last suspected movement was in 2006, and so rocks may move only about one millionth of the time," said Lorenz. "There is also evidence that the frequency of rock movement, which seems to require cold nights to form ice, may have declined since the 1970s due to climate change."

Richard and Jim Norris, and co-author Jib Ray of Interwoof started studying the Racetrack's moving rocks to solve the "public mystery" and set up the "Slithering Stones Research Initiative" to engage a wide circle of friends in the effort. They needed the help of volunteers who repeatedly visited the remote dry lake, quarried the rocks that were fitted with GPS, and maintained custom-made instruments. Lorenz and Brian Jackson of the Department of Physics at Boise State University started working on the phenomenon for their own reasons: They wanted to study dust devils and other desert weather features that might have analogs to processes happening on other planets.

"What is striking about prior research on the Racetrack is that almost everybody was doing the work not to gain fame or fortune, but because it is such a neat problem," said Jim Norris.

So is the mystery of the sliding rocks finally solved?

"We documented five movement events in the two and a half months the pond existed and some involved hundreds of rocks," says Richard Norris, "So we have seen that even in Death Valley, famous for its heat, floating ice is a powerful force in rock motion. But we have not seen the really big boys move out there….Does that work the same way?"

Home is where the microbes are

Date:

August 28, 2014

Source:

DOE/Argonne National Laboratory

Summary:

A person's home is their castle, and they populate it with their own subjects: millions and millions of bacteria. Scientists have detailed the microbes that live in houses and apartments. The results shed light on the complicated interaction between humans and the microbes that live on and around us. Mounting evidence suggests that these microscopic, teeming communities play a role in human health and disease treatment and transmission.

A person's home is their castle, and they populate it with their own subjects: millions and millions of bacteria.A study published tomorrow in Science provides a detailed analysis of the microbes that live in houses and apartments. The study was conducted by researchers from the U.S. Department of Energy's Argonne National Laboratory and the University of Chicago.

The results shed light on the complicated interaction between humans and the microbes that live on and around us. Mounting evidence suggests that these microscopic, teeming communities play a role in human health and disease treatment and transmission.

"We know that certain bacteria can make it easier for mice to put on weight, for example, and that others influence brain development in young mice," said Argonne microbiologist Jack Gilbert, who led the study. "We want to know where these bacteria come from, and as people spend more and more time indoors, we wanted to map out the microbes that live in our homes and the likelihood that they will settle on us.

"They are essential for us to understand our health in the 21^st century," he said.

The Home Microbiome Project followed seven families, which included eighteen people, three dogs and one cat, over the course of six weeks. The participants in the study swabbed their hands, feet and noses daily to collect a sample of the microbial populations living in and on them. They also sampled surfaces in the house, including doorknobs, light switches, floors and countertops.

Then the samples came to Argonne, where researchers performed DNA analysis to characterize the different species of microbes in each sample.

"We wanted to know how much people affected the microbial community on a house's surfaces and on each other," Gilbert said.

They found that people substantially affected the microbial communities in a house -- when three of the families moved, it took less than a day for the new house to look just like the old one, microbially speaking.

Regular physical contact between individuals also mattered -- in one home where two of the three occupants were in a relationship with one another, the couple shared many more microbes. Married couples and their young children also shared most of their microbial community.

Within a household, hands were the most likely to have similar microbes, while noses showed more individual variation.

Adding pets changed the makeup as well, Gilbert said -- they found more plant and soil bacteria in houses with indoor-outdoor dogs or cats.

In at least one case, the researchers tracked a potentially pathogenic strain of bacteria called Enterobacter, which first appeared on one person's hands, then the kitchen counter, and then another person's hands.

"This doesn't mean that the countertop was definitely the mode of transmission between the two humans, but it's certainly a smoking gun," Gilbert said.

"It's also quite possible that we are routinely exposed to harmful bacteria -- living on us and in our environment -- but it only causes disease when our immune systems are otherwise disrupted."

Home microbiome studies also could potentially serve as a forensic tool, Gilbert said. Given an unidentified sample from a floor in this study, he said, "we could easily predict which family it came from."

The research also suggests that when a person (and their microbes) leaves a house, the microbial community shifts noticeably in a matter of days.

"You could theoretically predict whether a person has lived in this location, and how recently, with very good accuracy," he said.

Researchers used Argonne's Magellan cloud computing system to analyze the data; additional support came from the University of Chicago Research Computing Center.

The study was funded by the Alfred P. Sloan Foundation. Additional funding also came from the National Institutes of Health, the Environmental Protection Agency, and the National Science Foundation.

Other Argonne researchers on the study included Argonne computational biologist Peter Larsen, postdoctoral researchers Daniel Smith, Kim Handley, and Nicole Scott, and contractors Sarah Owens and Jarrad Hampton-Marcell. University of Chicago graduate students Sean Gibbons and Simon Lax contributed to the paper, as well as collaborators from Washington University in St. Louis and the University of Colorado at Boulder.

Electric current to brain boosts memory: May help treat memory disorders from stroke, Alzheimer's, brain injury

Date:

August 28, 2014

Source:

Northwestern University

Summary:

Stimulating a region in the brain via non-invasive delivery of electrical current using magnetic pulses, called Transcranial Magnetic Stimulation, improves memory. The discovery opens a new field of possibilities for treating memory impairments caused by conditions such as stroke, early-stage Alzheimer's disease, traumatic brain injury, cardiac arrest and the memory problems that occur in healthy aging.

New research indicates that
stimulating a particular region in the brain
 via non-invasive delivery of electrical current
using magnetic pulses, called Transcranial Magnetic
Stimulation, improves memory.

Stimulating a particular region in the brain via non-invasive delivery of electrical current using magnetic pulses, called Transcranial Magnetic Stimulation, improves memory, reports a new Northwestern Medicine® study.The iscovery opens a new field of possibilities for treating memory impairments caused by conditions such as stroke, early-stage Alzheimer's disease, traumatic brain injury, cardiac arrest and the memory problems that occur in healthy aging.

"We show for the first time that you can specifically change memory functions of the brain in adults without surgery or drugs, which have not proven effective," said senior author Joel Voss, assistant professor of medical social sciences at Northwestern University Feinberg School of Medicine. "This noninvasive stimulation improves the ability to learn new things. It has tremendous potential for treating memory disorders."

The study will be published August 29 in Science.

The study also is the first to demonstrate that remembering events requires a collection of many brain regions to work in concert with a key memory structure called the hippocampus -- similar to a symphony orchestra. The electrical stimulation is like giving the brain regions a more talented conductor so they play in closer synchrony.

"It's like we replaced their normal conductor with Muti," Voss said, referring to Riccardo Muti, the music director of the renowned Chicago Symphony Orchestra. "The brain regions played together better after the stimulation."

The approach also has potential for treating mental disorders such as schizophrenia in which these brain regions and the hippocampus are out of sync with each other, affecting memory and cognition.

TMS Boosts Memory

The Northwestern study is the first to show TMS improves memory long after treatment. In the past, TMS has been used in a limited way to temporarily change brain function to improve performance during a test, for example, making someone push a button slightly faster while the brain is being stimulated. The study shows that TMS can be used to improve memory for events at least 24 hours after the stimulation is given.

Finding the Sweet Spot

It isn't possible to directly stimulate the hippocampus with TMS because it's too deep in the brain for the magnetic fields to penetrate. So, using an MRI scan, Voss and colleagues identified a superficial brain region a mere centimeter from the surface of the skull with high connectivity to the hippocampus. He wanted to see if directing the stimulation to this spot would in turn stimulate the hippocampus. It did.

"I was astonished to see that it worked so specifically," Voss said.

When TMS was used to stimulate this spot, regions in the brain involved with the hippocampus became more synchronized with each other, as indicated by data taken while subjects were inside an MRI machine, which records the blood flow in the brain as an indirect measure of neuronal activity.

The more those regions worked together due to the stimulation, the better people were able to learn new information.

How the Study Worked

Scientists recruited 16 healthy adults ages 21 to 40. Each had a detailed anatomical image taken of his or her brain as well as 10 minutes of recording brain activity while lying quietly inside an MRI scanner. Doing this allowed the researchers to identify each person's network of brain structures that are involved in memory and well connected to the hippocampus. The structures are slightly different in each person and may vary in location by as much as a few centimeters.

"To properly target the stimulation, we had to identify the structures in each person's brain space because everyone's brain is different," Voss said.

Each participant then underwent a memory test, consisting of a set of arbitrary associations between faces and words that they were asked to learn and remember. After establishing their baseline ability to perform on this memory task, participants received brain stimulation 20 minutes a day for five consecutive days.

During the week they also received additional MRI scans and tests of their ability to remember new sets of arbitrary word and face parings to see how their memory changed as a result of the stimulation. Then, at least 24 hours after the final stimulation, they were tested again.

At least one week later, the same experiment was repeated but with a fake placebo stimulation. The order of real stimulation and placebo portions of the study was reversed for half of the participants, and they weren't told which was which.

Both groups performed better on memory tests as a result of the brain stimulation. It took three days of stimulation before they improved.

"They remembered more face-word pairings after the stimulation than before, which means their learning ability improved," Voss said. "That didn't happen for the placebo condition or in another control experiment with additional subjects."

In addition, the MRI showed the stimulation caused the brain regions to become more synchronized with each other and the hippocampus. The greater the improvement in the synchronicity or connectivity between specific parts of the network, the better the performance on the memory test. "The more certain brain regions worked together because of the stimulation, the more people were able to learn face-word pairings, " Voss said.

Using TMS to stimulate memory has multiple advantages, noted first author Jane Wang, a postdoctoral fellow in Voss's lab at Feinberg. "No medication could be as specific as TMS for these memory networks," Wang said. "There are a lot of different targets and it's not easy to come up with any one receptor that's involved in memory."

The Future

"This opens up a whole new area for treatment studies where we will try to see if we can improve function in people who really need it," Voss said.

His current study was with people who had normal memory, in whom he wouldn't expect to see a big improvement because their brains are already working effectively.

"But for a person with brain damage or a memory disorder, those networks are disrupted so even a small change could translate into gains in their function," Voss said.

In an upcoming trial, Voss will study the electrical stimulation's effect on people with early-stage memory loss.

Voss cautioned that years of research are needed to determine whether this approach is safe or effective for patients with Alzheimer's disease or similar disorders of memory.

Ebola Outbreak in Sierra Leone Began at a Funeral

An extensive look at the genome of the Ebola virus reveals its behavior, when it arrived in West Africa and how it spread in the region to cause the largest-ever recorded Ebola outbreak.

Researchers sequenced 99 Ebola virus genomes from 78 patients in Sierra Leone, one of the countries affected by the outbreak that started in the neighboring Guinea, and found that the virus' genome changes quickly, including parts of the genome that are crucial for diagnostic tests to work.

"We've uncovered more than 300 genetic clues about what sets this outbreak apart from previous outbreaks," co-author Stephen Gire of Harvard said in a statement.

The first Ebola patient in Sierra Leone was identified in May. Investigations by the country's ministry of health traced the infection back to the funeral of a traditional healer who treated Ebola patients across the border in Guinea. The investigators found 13 additional cases of Ebola, all in women who attended the burial.

The researchers studied the viruses isolated from the blood of these patients, as well as subsequent Ebola patients, to identify the genetic characteristics of the Ebola virus responsible for this outbreak.

"Understanding how a virus is changing is critical knowledge for the development of diagnostics, vaccines and therapeutics, as they usually target specific parts of the viral genome that might change both between and within outbreaks," co-authors Kristian Andersen and Daniel Park of Harvard University told Live Science. [Ebola Virus: 5 Things You Should Know]

The findings suggest that the virus was brought to the region within the past decade, likely by an infected bat traveling from Central Africa. Earlier work had suggested the virus was circulating in animals in West Africa for several decades without having been detected.

The virus seems to have made a single jump from an animal to a person, and from there continued its journey through human-to-human transmission, the researchers said. This means that the current outbreak, at least in Sierra Leone, is not being fed by new transmissions from animals, in contrast to some previous Ebola outbreaks, which grew partly because of people's continuous exposure to infected animals.

This finding can guide decisions on whether to focus on human-to-human spread of the virus or on minimizing contact with animals, for example, by banning the consumption of bushmeat, the researchers said.

The study was published today (Aug. 28) in the journal Science.

Sierra Leone outbreak was traced to a funeral at the border

So far in the Ebola outbreak, 3,069 suspected and confirmed cases of infection and 1,552 deaths have been reported, according to the World Health Organization. The outbreak started in February 2014 in Guinea and then spread to Liberia, Nigeria and Sierra Leone. [Infographic: 2014 Ebola Outbreak]

The new study revealed that those first Ebola patients at the funeral were, in fact, infected by two distinct viruses.

"The thing that was most surprising was that two genetically different viruses were introduced into Sierra Leone at the same time, and likely through one event at a funeral," the researchers told Live Science.

Researchers were able to retrospectively look for the disease in blood samples and trace the trajectory of the virus because they were on the watch for another deadly disease, Lassa fever, said co-author Augustine Goba, director of the Lassa Laboratory at the Kenema Government Hospital. Goba was the doctor who identified the first Ebola case in Sierra Leone.

"We could thus identify cases and trace the Ebola virus spread as soon as it entered our country," Goba said.

Nearly 60 co-authors from several countries helped collect samples and analyze the genome of the virus. Five of them contracted Ebola in the course of their work in the epicenters of the outbreak and died from the disease before the publication of the study.

"There is an extraordinary battle still ahead, and we have lost many friends and colleagues already, like our good friend and colleague Dr. Humarr Khan, a co-senior author here," said co-senior author Pardis Sabeti, an associate professor at Harvard.

There are no vaccines to prevent infection with Ebola virus or drugs to cure the disease. An experimental treatment based on antibodies, called ZMapp, has shown promise in monkeys but it's unclear whether the drug is also effective in treating people.

Lobotomy: Definition, Procedure & History

Lobotomy, also known as leucotomy, is a neurosurgical operation that involves severing connections in the brain's prefrontal lobe, according to Encyclopaedia Britannica. Lobotomies have always been controversial, but were widely performed for more than two decades as treatment for schizophrenia, manic depression and bipolar disorder, among other mental illnesses.

Lobotomy was an umbrella term for a series of different operations that purposely damaged brain tissue in order to treat mental illness, said Dr. Barron Lerner, a medical historian and professor at NYU Langone Medical Center in New York.

"The behaviors [doctors] were trying to fix, they thought, were set down in neurological connections," Lerner told Live Science. "The idea was, if you could damage those connections, you could stop the bad behaviors."

When lobotomy was invented, there were no good ways to treat mental illness, and people were looking for "pretty desperate" kinds of interventions, he said. Even so, there were always critics of the procedure, he added.

History

Doctors first began manipulating the brain to calm patients in the late 1880s, when the Swiss physician Gottlieb Burkhardt removed parts of the cortex of the brains of patients with auditory hallucinations and other symptoms of schizophrenia, noting that it made them calm (although one patient died and another committed suicide after the procedure), according to Encyclopaedia Britannica.

The Portuguese neurologist António Egas Moniz is credited with inventing the lobotomy in 1935, for which he shared the Nobel Prize for Physiology or Medicine in 1949 (later, a movement was started to revoke the prize, unsuccessfully).

Yale neuroscientist John Fulton and his colleague Carlyle Jacobsen had performed lobotomy-like procedures on chimpanzees in 1935. Moniz and his colleague Almeida Lima performed the first human experiments later that year. The frontal lobes were targeted because of their association with behavior and personality.

Moniz reported the treatment as a success for patients with conditions such as depression, schizophrenia, panic disorder and mania, according to an article published in 2011 in the Journal of Neurosurgery. But the operations had severe side effects, including increased temperature, vomiting, bladder and bowel incontinence and eye problems, as well apathy, lethargy, and abnormal sensations of hunger, among others. The medical community was initially critical of the procedure, but nevertheless, physicians started using it in countries around the world. 

Methods

The first procedures involved cutting a hole in the skull and injecting ethanol into the brain to destroy the fibers that connected the frontal lobe to other parts of the brain. Later, Moniz introduced a surgical instrument called a leucotome, which contains a loop of wire that, when rotated, creates a circular lesion in the brain.

Italian and American doctors were early adopters of the lobotomy. The American neurosurgeons Walter Freeman and James Watts adapted Moniz's technique to create the "Freeman-Watts technique" or the "Freeman-Watts standard prefrontal lobotomy," according to Encyclopaedia Britannica.

The Italian psychiatrist Amarro Fiamberti first developed a procedure that involved accessing the frontal lobes through the eye sockets, which would inspire Freeman to develop the transorbital lobotomy in 1945, a method that would not require a traditional surgeon and operating room. The technique involved using an instrument called an orbitoclast, a modified ice pick, which the physician would insert through the patient's eye socket using a hammer. They would then move the instrument side-to-side to separate the frontal lobes from the thalamus, the part of the brain that receives and relays sensory input.

Freeman wasn't just a neurologist, he was a showman, Lerner said. "He traveled around the country, doing multiple lobotomies in a day," he said. "He absolutely did this for way too long."

Prevalence & effects

About 50,000 lobotomies were performed in the United States, and Freeman himself performed between 3,500 and 5,000.

While a small percentage of people supposedly got better or stayed the same, for many people, lobotomy had negative effects on a patient's personality, initiative, inhibitions, empathy and ability to function on their own.

"The main long-term side effect was mental dullness," Lerner said. People could no longer live independently, and they lost their personalities, he said.

Mental institutions played a critical role in the prevalence of lobotomy. At the time, there were hundreds of thousands of mental institutions, which were overcrowded and chaotic. By giving unruly patients lobotomies, doctors could maintain control over the institution, Lerner said.

That's exactly what happens in the 1962 novel and 1975 film "One Flew Over the Cuckoo's Nest," in which Randall Patrick McMurphy, a rambunctious but sane man living in a mental hospital, is given a lobotomy that leaves him mute and vacant-minded.

"Usually things in movies are exaggerated," Lerner said. But in this case, it was "disturbingly real," he said.

The practice started subsiding in the mid-1950s, as scientists developed antipsychotic and antidepressant medications that were much more effective. Nowadays, mental illness is primarily treated with drugs. In cases where drugs are not effective, people may be treated with electroconvulsive therapy, a procedure that involves passing electrical currents through the brain to trigger a brief seizure, according to the Mayo Clinic. 

Lobotomy is rarely, if ever, performed today, and if it is, "it’s a much more elegant procedure," Lerner said. "You're not going in with an ice pick and monkeying around." The removal of specific brain areas (psychosurgery) is only used to treat patients for whom all other treatments have failed.

What Is Civil Engineering?

Civil engineering is the design and construction of public works, such as dams, bridges and other large infrastructure projects. It is one of the oldest branches ofengineering, dating back to when people first started living in permanent settlements and began shaping their environments to suit their needs. 

Early engineers built walls, roads, bridges, dams and levees; they dug wells, irrigation ditches and trenches. As larger groups of people began living together in towns and cities, these populations needed reliable sources of clean water, the means to dispose of waste, a network of streets and roadways for commerce and trade, and a way to defend themselves against hostile neighbors. 

Ancient civil engineering projects include the roads of the Roman Empire, the Great Wall of China, the cliff dwellings at Mesa Verde and Mayan ruins at Copan, Palenque and Tikal. Many early civilizations built monuments to their rulers or gods. These may have been simple mounds or truly remarkable achievements, such as the Pyramids of Giza and Stonehenge, whose construction by pre-industrial societies remains mysterious. The names of the engineers who designed these wonders are lost to antiquity. 

Today, the public is more likely to remember the names of great civil engineering projects than the names of the engineers who designed and built them. These include the Brooklyn Bridge (designed by John August Roebling and son Washington Roebling), the Hoover Dam (John L. Savage), the Panama Canal (John Frank Stevens) and the Golden Gate Bridge (Joseph Strauss and Charles Ellis). One notable exception is theEiffel Tower, named after Gustave Eiffel, the French civil engineer whose company built it. 

What does a civil engineer do?

Civil engineers "design, construct, supervise, operate and maintain large construction projects and systems, including roads, buildings, airports, tunnels, dams, bridges, and systems for water supply and sewage treatment," according to the U.S. Bureau of Labor Statistics(BLS). 

These engineers may also handle site preparation activities, such as excavation, earth moving and grading for large construction projects. Additionally, civil engineers may conduct or write the specifications for destructive or nondestructive testing of the performance, reliability and long-term durability of materials and structures. 

Here are some recent and ongoing civil engineering projects of note:

• A team of researchers from Johns Hopkins University conducted tests to see how well buildings made of cold-formed steel can withstand earthquakes. 
• Engineers at the University of Maryland are working on smart bridges that can send out warnings when they are in danger of collapsing.
• In Los Angeles, civil engineers who are experts in structural monitoring helped art conservators preserve the iconic Watts Towers monument.

What a civil engineer needs to know

Today's civil engineers need in-depth understanding of physics, mathematics, geology and hydrology. They must also know the properties of a wide range of construction materials, such as concrete and structural steel, and the types and capabilities of construction machinery. With this knowledge, engineers can design structures that meet requirements for cost, safety, reliability, durability and energy efficiency. Civil engineers also need a working knowledge of structural and mechanical engineering. 

These engineers can be involved in nearly every stage of a major construction project. That can include site selection, writing specifications for processes and materials, reviewing bids from subcontractors, ensuring compliance with building codes, and supervising all phases of construction from grading and earth moving to painting and finishing. 

More and more, civil engineers rely on computer-aided design (CAD) systems; therefore, proficiency with computers is essential. In addition to speeding up the drafting process for civil engineering projects, CAD systems make it easy to modify designs and generate working blueprints for construction crews. A comprehensive list of necessary skills and abilities for civil engineers can be found at MyMajors.com. 

Civil engineering jobs & salary

The BLS states, "Civil engineers generally work indoors in offices. However, many spend time outdoors at construction sites so they can monitor operations or solve problems onsite." Most civil engineers employed in the private sector work for large construction contractors or as consultants. Government institutions that employ civil engineers include state transportation departments and the military. 

Most civil engineering jobs require at least a bachelor's degree in engineering. Many employers, particularly those that offer engineering consulting services, also require state certification as a professional engineer. Additionally, many employers require certification from theAmerican Society of Civil Engineers (ASCE). A master's degree is often required for promotion to management, and ongoing education and training are needed to keep up with advances in technology, equipment, computer hardware and software, building codes, and other government regulations. 

According to Salary.com, as of July 2014, the salary range for a newly graduated civil engineer with a bachelor's degree is $55,570 to $73,908. The range for a mid-level engineer with a master's degree and five to 10 years of experience is $74,007 to $108,640, and the range for a senior engineer with a master's degree or doctorate and over 15 years of experience is $97,434 to $138,296. Many experienced engineers with advanced degrees are promoted to management positions or start their own businesses where they can earn even more. 

The future of civil engineering

Employment of civil engineers is projected to grow 20 percent from now to 2022, faster than the average for all occupations, according to the BLS. "As infrastructure continues to age, civil engineers will be needed to manage projects to rebuild bridges, repair roads, and upgrade levees and dams," the BLS said. There should be many opportunities for qualified applicants, particularly those who have kept abreast of the latest developments in technology and regulations. Having good grades from a highly rated institution should give a job seeker an advantage over the competition. 

Three Things You Didn’t Know About the Arachnids That Live on Your Face

You are not alone. Your body is a collection of microbes, fungi, viruses…and even other animals. In fact, you aren’t even the only animal using your face. Right now, in the general vicinity of your nose, there are at least two species of microscopic mites living in your pores. You would expect scientists to know quite a lot about these animals (given that we share our faces with them), but we don’t.

Here is what we do know: Demodex mites are microscopic arachnids (relatives of spiders and ticks) that live in and on the skin of mammals – including humans. They have been found on every mammal species where we’ve looked for them, except the platypus and their odd egg-laying relatives.

Often mammals appear to host more than one species, with some poor field mouse species housing four mite species on its face alone. Generally, these mites live out a benign coexistence with their hosts. But if that fine balance is disrupted, they are known to cause mange amongst our furry friends, and skin ailments like rosacea and blepharitis in humans. Most of us are simply content – if unaware – carriers of these spindly, eight-legged pore-dwellers.

Scientists from NC State, the North Carolina Museum of Natural Sciences, and the California Academy of Sciences have just published a study that uncovers some previously unknown truths regarding these little-known mites – all the while providing a glimpse into even bigger mysteries that have yet to be solved.

1. Everyone has mites.

One of our most exciting discoveries is that these mites are living on everyone. Yes everyone (even you). This hasn’t always been obvious because it can be hard to find a microscopic mite living on one’s face. Traditional sampling methods (including scraping or pulling a piece of tape off your face) only return mites on 10-25 percent of adults. The fact that mites are found at a much higher rate on cadavers (likely because the dead are easier to sample more extensively and intrusively) was a hint that they might be much more ubiquitous.

As it turns out, you don’t have to actually see a mite to detect its presence. Dan Fergus, a mite molecular biologist at the North Carolina Museum of Natural Sciences, discovered that mite DNA could be sequenced from face scrapings regardless of whether a mite could be found under the microscope. And mite DNA was sequenced from every adult we sampled. Meaning that if you let us scrape your face, we’d find mite DNA on you as well. And where mite DNA is found, you’ll find mites. 

2. Humans host two mite species that aren’t closely related to each other.

One of the most intriguing (and unsolved) face mite mysteries is how humans acquired these beasties. Perhaps these mites are a model system of co-evolution. It’s possible that as every species of mammal evolved, so did their mites – each one particularly adapted to its changed environs. In such a case, we would expect that we acquired our mites from our ape ancestors, and that the two species of human mites would be more closely related to each other than to any other mite species.

However, we’ve learned that the two mite species on our faces Demodex folliculorum(the long skinny one, pictured at the top of this post) and Demodex brevis (the short, chubby one, photo to the right) are actually not very close relatives to each other at all. Our analyses actually show that brevis is more closely related to dog mites than tofolliculorum, the other human mite. This is interesting because it shows us that humans have acquired each of these mite species in different ways, and that there are two separate histories of how each of these mite species came to be on our face.

Though we don’t have enough evidence to say that we got one of our mites from man’s best friend, it does seem possible that one of the domestic animal species that we’ve long shared our lives with (be it dogs, goats or otherwise) may have gifted us their mites.

3. Mites can tell us about the historical divergence of human populations

How we acquired our mites is just one part of the story. We are also curious about how our mite species have evolved since they became our constant companions.

Demodex have likely been living with us for a long, long time; as early humans walked out of Africa and found their way around the globe, they probably carried their mites with them. So we want to know if Demodex DNA can provide a reflection of our own evolutionary history by allowing us to retrace those ancient paths of human migration.

So far, our analyses look promising. When looking at the DNA from one of our mite species, D. brevis, we found that mites from China are genetically distinct from mites from the Americas. East Asians and European populations diverged over 40,000 years ago and so far it looks like their mites did as well. On the other hand, D. folliculorumfrom China is indistinguishable from that of the Americas. Of the two Demodexspecies associated with humans, D. brevis lives deeper in your pores than folliculorumand is probably shared between people less readily, whereas D. folliculorum appears to enjoy global domination.

But as exciting as these results are, China and the US are just a small piece of the picture. We can’t wait to see what happens when we sample D. brevis from people all over the world! The ancient journey of Homo sapiens as retold by mites.

If reading this made your face a little itchy, rest easy. In an evolutionary perspective, humans and Demodex are old, old friends. You are in good company. And so are your mites.

Editor’s Note: This is a guest post by Michelle Trautwein, adjunct assistant professor of entomology at NC State and Schlinger Chair of Dipterology at the California Academy of Sciences.

The paper, “Ubiquity and diversity of human associated Demodex mites,” is published in PLOS ONE. Lead author of the paper is Megan Thoemmes, a Ph.D. student at NC State. Co-authors include Trautwein, Fergus, Julie Urban of the North Carolina Museum of Natural Sciences, and Rob Dunn, an associate professor of biology at NC State. The research was supported by NASA, under grant ROSES NNX09AK22G, and the National Science Foundation, under grant 0953390.

Suicide is Not 'Unavoidable

Everyone has their share of bad days, but when feelings such as worthlessness, helplessness, or hopelessness become predominant in everyday life, there may be a more serious issue at hand.

According to the U.S. Centers for Disease Control and Prevention (CDC), mental illness is responsible for more disability than any other specific illness in developed countries, with about 25 percent of all U.S. adults suffering from some sort of mental illness and nearly 50 percent of adults experiencing at least one mental illness during their lifetime. Depression, in particular, is a whole-body source of suffering and disability that can alter the way a person thinks, feels, and acts. Although deceptively common, depression is often tragically linked to suicide.

In fact, within the past decade, suicide rates in the United States significantly increased after a previous decade of decline. It's not clear why this is, but it's probably not just from one reason. And that's the challenge presented by suicide — it's a multifaceted problem that requires multifaceted solutions. The passing of Hollywood icon Robin Williams recently shed light on how profoundly depression can affect an individual's life. Williams, arguably one of America's favorite actors, killed himself in his own home after a lifelong struggle with depression, drug addiction and alcoholism, complicated by the recent diagnosis of Parkinson's disease. 

At face value, not many people would have guessed that he had suffered so terribly and for so long. A revered actor, he endeared himself to the world, not just by virtue of his comic genius, but also by his warmth and sweetness of character. While his death seems especially cruel in reminding us that mental illness has the potential to undermine anyone, it also creates an opportunity to share the news that depression is highly treatable and that suicide is preventable. 

Unfortunately, depression is a widely misunderstood and stigmatized disease. Although excellent treatments are available and it is the rare individual who will not respond to treatment, sometimes even wealth, resources and connections are insufficient in engaging sufferers with the good treatment they deserve. 

For example, suicide rates for middle-aged white men — who tend to have the resources at hand to treat their disease — have gone up tremendously in the last ten years, though researchers have not pinpointed the exact reason why. That said, based on what we now know about treatment, we should be unwilling to accept even a single suicide as being unavoidable. 

Depression is not the same as just being in a bad or unhappy mood. The diagnosis depends on a combination of symptoms that are sufficiently severe to impair an individual's day-to-day functions. Recognizing depression is crucial to helping people heal, although signs of depression can be tricky to spot or easily dismissed as "normal." 

There are a few common signs of depression to look out for. Contact your primary health care provider if you begin to notice changes in ourself, or a loved one, such as:

Often feeling depressed, down, sad, angry or irritable.

Loss of interest and pleasure in activities formerly enjoyed.

• Noticeable increase or decrease in appetite or weight, not attributable to dieting or deliberate effort. 
• Noticeable change in sleep pattern, such as fitful sleep, difficulty falling or staying asleep, early morning awakening, or sleeping more than usual.
• Fatigue or loss of energy. 
• Being noticeably slowed down or agitated in thinking or behavior.
• Inappropriate or excessive feelings of worthlessness or guilt.
• Diminished ability to concentrate or make decisions.
• Recurrent thoughts of death or suicide. 

It is also common for people who are depressed to feel overwhelmed and to suffer from otherwise unexplained, but real physical symptoms like headache, gastrointestinal distress or chronic pain. 

Depression can also sometimes distort thinking and generate unrealistic beliefs, a condition known as psychotic depression that can be reversed with treatment. 

Because each patient dealing with depression is unique, treatment must be individualized. This is especially true when "first line" treatments, such as psychotherapy or an antidepressant, alone are not successful. In such circumstance, a careful evaluation for potential medical causes of depression can be helpful, and it is often useful to combine modern psychotherapy and antidepressant medication, as science tells us that the combination of medication and psychotherapy is typically superior to either treatment alone. 

We also know that skillfully changing or combining antidepressants can produce potentially life-changing results. Even more exciting are new treatments that make use of weak electrical current and magnetic fields to improve mood and return individuals to health. 

Here at Ohio State's Wexner Medical Center, we offer treatments such as transcranial magnetic stimulation (TMS), as well as a modern, safe and effective version of electroconvulsive therapy (ECT). Depressed individuals who are discouraged by lack of progress need to understand that promising treatments are available, and that the persistence of patients and doctors is most often rewarded with success.

Depression is a serious illness that requires and deserves immediate care. If you or anyone you know thinks they may be suffering from depression, get ahead of the illness early to ensure a promising and happy future. Treatment really can make a difference and even prove lifesaving. 

New Dates for Prehistoric Paintings in Utah’s Great Gallery

LOGAN, UTAH— A team led by Utah State University geologist Joel Pederson has used luminescence dating techniques to document the timing of geologic events in southern Utah’s Canyonlands National Park, and thus “draw a box” around a probable window of time for the creation of the paintings in Horseshoe Canyon’s Great Gallery. “The most accepted hypotheses pointed to the age of these paintings as 2,000 to 4,000 years old or perhaps even 7,000 to 8,000 years old. Our findings reveal these paintings were likely made between 1,000 and 2,000 years ago,” Pederson told Phys.org. The new dates suggest that the artists may have co-existed with the Fremont people, who are known for their carved pictographs. “Previous ideas suggested a people different from the Fremont created the paintings because the medium and images are so different. This raises a lot of archaeological questions,” Pederson explained. To learn more about art from this period in Southwestern prehistory, see "Investigating A Decades-Old Disapperance," ARCHAEOLOGY's account of a mystery involving Fremont figurines.

Who Crafted Saudi Arabia’s 100,000-Year-Old Stone Tools?

BORDEAUX, FRANCE—A team of researchers led by Eleanor Scerri of the University of Bordeaux compared stone artifacts unearthed from three sites in the Arabian Desert with artifacts discovered in northeast Africa near the skeletons of modern humans. All of the tools were between 70,000 and 125,000 years old. Live Science reports that the artifacts from two of the three Arabian sites were “extremely similar” to the tools from northeast Africa, suggesting that the groups may have had some interaction, and that the Arabian tools could have been made by modern humans. The tools from the third Arabian site were “completely different,” however, and may have been crafted by a different human lineage. “It seems likely that there were multiple dispersals into the Arabian Peninsula from Africa, some possibly very early in the history of Homo sapiens. It also seems likely that there may have been multiple dispersals into this region from other parts of Eurasia. These features are what make the Arabian Peninsula so interesting,” Scerri explained. To see how this discovery might complement recent DNA work, see ARCHAEOLOGY's "Turning Back the Human Clock."

Turning Back the Human Clock

For years, archaeologists and geneticists have been troubled by the fact that their time lines for key events in human evolution don’t always match up. While archaeologists rely on the dating of physical remains to determine when and how human beings spread across the globe, geneticists use a DNA “clock” based on the assumption that the human genome mutates at a constant rate. By comparing differences between modern and ancient DNA, geneticists then calculate when early humans diverged from other species and when human populations formed different genetic groups.

The DNA clock is a powerful tool, but its conclusions—for example, that modern humans first emerged from Africa about 60,000 years ago—can disagree with archaeological evidence that shows signs of modern human activity well before that date at sites in regions as far-flung as Arabia, India, and China.

Now, new work, based on observation of the genetic differences between present-day parents and children, suggests that the genetic clock may actually run about twice as slowly as previously believed, at least for the last million years or so of primate history. In their review paper in the journal Nature Reviews Genetics, Aylwyn Scally and Richard Durbin of the Wellcome Trust Sanger Institute in Hinxton, England, propose much earlier dates for watershed events in human evolution, which could help bring the genetic and archaeological records in line. For instance, a slower clock places the migration of modern humans out of Africa at around 120,000 years ago, which is more consistent with archaeological evidence.

The revised clock also supports archaeological signs of modern human activity from more than 60,000 years ago at sites such as Jwalapuram, India (“Stone Age India,” January/February 2010), and Liujiang, China—evidence that has often been dismissed by geneticists as impossible. While more work is needed to confirm the findings, Scally says that archaeologists who work on such sites should be excited: “It can no longer be said that the genetic evidence is unequivocally against them.”