Lying makes you feel dirty. For a 2010 study, Norbert Schwarz, of the University of Michigan psychology department, asked participants to imagine they were competing for a job, and then falsely deny that they had found a document that would help a competitor. Afterwards, as part of a purported marketing survey, the people rated mouthwash, hand sanitizer and other products. Participants who lied on the phone felt a stronger desire for mouthwash; those who lied on e-mail favored hand sanitizer. “This study shows how ‘concrete’ the metaphorical links are between abstract and concrete domains of life,” Schwarz said via press release. “Not only do people want to clean up after a dirty deed, they want to clean the specific body part involved.”1
Not lying makes you healthy. Telling the truth when tempted to lie can significantly improve mental and physical health, according to a 2012 study. “Recent evidence indicates that Americans average about 11 lies per week. We wanted to find out if living more honestly can actually cause better health,” said Anita Kelly, professor of psychology at the University of Notre Dame in a press release. “We found that the participants could purposefully and dramatically reduce their everyday lies, and that in turn was associated with significantly improved health.” Weekly self-reports of mental and physical health for both the control group and the group instructed to stop telling lies improved if they told fewer lies. The link was stronger for the no-lie folks, who also began to see themselves as more honest during the 10-week experiment.
Writing lies leaves traces. A 2009 study at the University of Haifa, Israel, found differences in pen movement and pressure when people wrote the truth compared to fiction. Study participants who were asked to lie pressed harder on the pen, and altered the height and length of their letters. The researchersconcluded that liars spend more mental effort controlling behavior that is normally automatic, altering the mechanics and outcome of writing.
Some parents “parent by lying.” American parents often say “honesty is the best policy,” but they often lie to their kids, according to research2 by Gail Heyman, professor of psychology at the University of California San Diego. In one case, a mother told her child that if he didn’t finish all of his food he would get pimples. College students told the researchers their parents had lied to them yet proclaimed that lying was wrong. “We are surprised … even the parents who most strongly promoted the importance of honesty with their children engaged in parenting by lying,” co-author Kang Lee, of the University of Toronto, said in a press release.
You may miss an online lie. In a recent study of online dating3, Catalina Toma, an assistant professor of communication arts at University of Wisconsin-Madison, found that would-be daters tended to skirt topics like weight or age that they’d lied about in their online profile, probably trying to deflect attention from the lie. The mental demands of concocting untruths likely explained the comparative brevity of liar’s self-descriptions. The study found that software, but not living humans, could sort legit profiles from phonies.
The materials, called perovskites, are particularly good at absorbing visible light, but had never been studied in their purest form: as perfect single crystals.
Using a new technique, researchers grew large, pure perovskite crystals and studied how electrons move through the material as light is converted to electricity.
Led by Professor Ted Sargent of The Edward S. Rogers Sr. Department of Electrical & Computer Engineering at the University of Toronto in collaboration with Professor Osman Bakr of the King Abdullah University of Science and Technology (KAUST), the team used a combination of laser-based techniques to measure selected properties of the perovskite crystals.
By tracking down the ultrafast motion of electrons in the material, they have been able to measure the diffusion length – how far electrons can travel without getting trapped by imperfections in the material – as well as mobility – how fast the electrons can move through the material. Their work was published this week in the journal Science.
A perovskite crystal.UNIVERSITY OF TORONTO“Our work sets the bar for the ultimate solar energy-harvesting performance of perovskites,” says Riccardo Comin, a post-doctoral fellow with the Sargent Group. “With these materials it’s been a race to try to get record efficiencies, and there are no signs of stopping or slowing down.”
In recent years, perovskite efficiency has soared to over 20 per cent, very close to the current best performance of commercial-grade silicon-based solar panels you see mounted in Spanish deserts and on Californian roofs.
“In terms of efficiency, perovskites are perfectly comparable or better than materials that have already been commercialized,” says Valerio Adinolfi, a PhD candidate in the Sargent Group and co-first author on the paper. “The challenge is to make solar attractive from the business side. It’s not just matter of making it efficient – the point is to make it efficient and cheap.”
The study has obvious implications for green energy, but may also enable innovations in lighting.
Think of a solar panel made of perovskite crystals as a fancy slab of glass: light hits the crystal surface and gets absorbed, exciting electrons in the material. Those electrons travel easily through the crystal to electrical contacts on its underside, where they are collected in the form of electric current.
Now imagine the sequence in reverse – power the slab with electricity, inject electrons and release energy as light. A more efficient electricity-to-light conversion means perovskites could open new frontiers for energy-efficient LEDs.
Parallel work in the Sargent Group focuses on improving nano-engineered solar-absorbing particles called colloidal quantum dots. “Perovskites are great visible-light harvesters, and quantum dots are great for infrared,” said Sargent.
“In future, we will explore the opportunities for stacking together complementary absorbent materials,” says Dr. Comin. “There are very promising prospects for combining perovskite work and quantum dot work for further boosting the efficiency.”
POSTED: 01/30/2015 02:46:00 PM PST1 COMMENT| UPDATED: ABOUT 3 HOURS AGO
NEW YORK — In the world of e-books, you largely have a choice between Amazon’s Kindle and everyone else.
Amazon.com distributes its e-books in a proprietary format that isn’t compatible with other devices and systems. Other companies have embraced a format called EPub. In theory, that means books bought for one non-Kindle device can be read on another.
This is important because the device you own today might not be the one you’ll want five years from now. You won’t want to buy all your e-books again.
Unfortunately, trying to move my EPub books around gets frustrating. I should be able to read on Barnes & Noble’s Nook devices the books I’ve legitimately bought for Kobo devices, for instance. But it isn’t easy to figure out how to do. Instructions, if any, tend to focus on how to bring in books bought elsewhere, not how to move them out. And it took lots of Google searches to find some missing steps.
I’ll go through a few examples:
READING KOBO E-BOOKS ON A NOOK
To its credit, Kobo’s help section offers instructions on exporting its books to other devices: “Transfer Kobo eBooks to non-Kobo eReaders by using Adobe Digital Editions.” It goes on to explain that Adobe Digital Editions is a free app “that you can use to read Kobo books and transfer them to a non-Kobo eReader.”
It took more digging to find out what that was about.
I went to Adobe’s website to get Digital Editions for my Windows computer. I succeeded in moving “Catching Fire” from my Kobo account to that computer. But to read it on a Nook GlowLight e-reader, I had to connect the device to the computer and authorize it with my Adobe ID. It took a few tries to get that right. I then had to drag the file to the Nook and disconnect the e-reader.
I tried that with a Nook tablet from Samsung, but I couldn’t authorize it through Digital Editions. I found a way to add my Adobe ID by going through the Nook settings on the device — not the regular settings. Once I did that, I couldn’t find a way to sign out.
READING NOOK E-BOOKS ON A KOBO
You couldn’t simply reverse the steps because the Nook doesn’t use Adobe’s copy-protection technology. It has its own.
Fortunately, later versions of Digital Editions support the Nook system, but it takes some extra steps.
After downloading a Nook version of “Allegiant” to the Windows computer, Digital Editions told me I needed an “unlock code.” What’s that? I tried my Nook username and password. That didn’t work. It took some Googling to find a clue in some online forum: It’s the name on my Barnes & Noble account and the default credit card number. OK, that worked.
I then transferred the book to a Kobo Aura e-reader. But I couldn’t read it. Turned out the Aura had an older version of Digital Editions, while only the newer ones support Nook’s copy protection.
WORKING WITH APPLE’S IBOOKS
I bought the “Game of Thrones” series from the Apple iBookstore, but Apple’s copy protection doesn’t work with non-Apple devices. Apple does make it easy to bring EPub books bought elsewhere — as long as they are free of copy protection. But that eliminates Nook, Kobo and many other e-books.
Digital music used to be this way, until recording companies started selling songs without copy protection. Most e-books still have copy protection. Outside software is available to break the locks on EPub and Kindle books, but the legality is questionable.
In a sense, the walls Amazon has built with Kindle aren’t so bad after all. Although Kindle books won’t work on dedicated e-readers, Amazon makes Kindle apps for just about every other device, including Samsung’s Nook tablet and Apple’s iPad.
Ultimately, trying to transfer books with Adobe software might be useful only when borrowing e-books from a library or commercial service. Otherwise, the headaches aren’t worth it. It’s easier, for instance, just to install a Nook, Kobo or Kindle app on an iPad. This approach won’t help if you use e-readers, but it should work with most phones and tablets.
More precise mapping of how individual neurons interact in the brain
January 30, 2015
Researchers at the UNC School of Medicine have used new deep-brain imaging techniques to link the activity of individual, genetically similar neurons to particular behaviors of freely moving mice.
For the first time ever, scientists watched as one neuron was activated when a mouse searched for food while a nearly identical neuron next to it remained inactive; instead, the second neuron only became activated when the mouse began eating.
This work, published in the journal Cell, suggests that manipulating an entire genetically defined subtype of neurons to treat a condition, such as binge-eating, might be too broad of an approach. Drug developers might have to focus on one type of cell within the subset to avoid potentially serious side effects.
This study, led by Garret Stuber, PhD, assistant professor of psychiatry, is one of the first published reports using novel technologies that support the NIH BRAIN Initiative to map how individual neurons and neural circuits interact throughout the brain.
“Traditional imaging techniques wouldn’t allow us to record this kind of activity deep inside the brains of freely moving mice,” said Stuber, who is also a member of the UNC Neuroscience Center.
“For the first time, we can view specific, genetically defined neurons in the lateral hypothalamus as they light up while the mice search out food, eat, and drink.”
The finding suggests that targeting an entire subpopulation of brain cells to learn about their functions can be somewhat misleading.
“This is important to know because if we want to create a drug treatment for obesity, for instance, then you wouldn’t want to affect cells involved in appetite because you might affect cells involved in other aspects of motivated behavior,” said Stuber. “But if we could target only the cells involved in consumption, then maybe we could modulate only those cells without affecting motivation.”
For more than 50 years, scientists have known that basic motivated behaviors, such as eating, drinking, and sleeping, are controlled within the lateral hypothalamus, which is similar in all mammals.
Later studies showed that electrically stimulating the lateral hypothalamus enhanced motivation – the “wanting” of some kind of basic outcome – such as the motivation to eat. Then, researchers found that this brain region is responsible for eating. That is, if there’s food, animals will eat it if this brain region is electrically stimulated. It doesn’t matter if the animals are hungry or not.
But stimulating an entire brain region can’t tell researchers which cell type is truly responsible for which behavior. Until recently, scientists were unable to study these different kinds of cells as they relate to certain kinds of behavior. Stuber decided to use various techniques, including optogenetics and calcium imaging, to study the roles of GABAergic neurons – a large subset of neurons in the lateral hypothalamus.
But the question was: which specific neurons were encoding the various behaviors?
To find out, Stuber’s team first modified only the GABAergic neurons to glow fluorescent when calcium enters neurons (which is what happens during bursts of neuronal activity) to see when they would be activated.
These microscopes, about one inch long, are attached to the brains of mice, which are then able to move and behave normally without restrictions. So Stuber’s team was able to study 740 GABAergic neurons in live mice.
Stuber’s team then conducted experiments to analyze the neurons that fired during motivated behaviors, such as searching for food, and the neurons that fired during consummatory behaviors, such as eating and drinking.
When mice searched for food, approximately 22 percent of GABAergic neurons were activated. When the mice consumed food or drink, about 10 percent of the GABAergic neurons fired.
“The key for us is that there was nearly no overlap,” Stuber said. There were cells that only fired during motivated behaviors and cells that only fired during consummatory behaviors.
“When it comes to how these cells function in the brain, we found that there are subpopulations of cells within this larger network of GABAergic neurons,” Stuber said. “And these individual cells are responsible for these highly intertwined activities.
“At some point, we’ll have to be able to target smaller and smaller subpopulations of neurons. The idea is to find genetic markers to delineate these distinct groups of cells. If so, then we could target these groups and learn a lot more about what they do and how they do it.”
UNC Health Care | Neurons firing in hippocampus
This research was funded by the National Institutes of Health, the Klarman Family Foundation, The Foundation for Prader-Willi Research, and the department of psychiatry in the UNC School of Medicine.
Abstract for Visualizing hypothalamic network dynamics for appetitive and consummatory behaviors
Optimally orchestrating complex behavioral states, such as the pursuit and consumption of food, is critical for an organism’s survival. The lateral hypothalamus (LH) is a neuroanatomical region essential for appetitive and consummatory behaviors, but whether individual neurons within the LH differentially contribute to these interconnected processes is unknown. Here, we show that selective optogenetic stimulation of a molecularly defined subset of LH GABAergic (Vgat-expressing) neurons enhances both appetitive and consummatory behaviors, whereas genetic ablation of these neurons reduced these phenotypes. Furthermore, this targeted LH subpopulation is distinct from cells containing the feeding-related neuropeptides, melanin-concentrating hormone (MCH), and orexin (Orx). Employing in vivo calcium imaging in freely behaving mice to record activity dynamics from hundreds of cells, we identified individual LH GABAergic neurons that preferentially encode aspects of either appetitive or consummatory behaviors, but rarely both. These tightly regulated, yet highly intertwined, behavioral processes are thus dissociable at the cellular level.
MIT scientists have developed a new method of coping with the complexity of studying the brain.
They created probes containing biocompatible multipurpose fibers about 85 micrometers in width (about the width of a human hair).
The new fibers can deliver optogenetic signals and drugs directly into the brain, while allowing simultaneous electrical readout to continuously monitor the effects of the various inputs from freely moving mice.
The new fibers are made of polymers that closely resemble the characteristics of neural tissues — they are “soft and flexible and look more like natural nerves,” according to MIT assistant professor of materials science and engineering Polina Anikeeva — allowing them to stay in the body much longer without harming the delicate tissues around them.
Devices currently used for neural recording and stimulation, she says, are made of metals, semiconductors, and glass, which can damage nearby tissues during ordinary movement.
“It’s a big problem in neural prosthetics,” she says. “They are so stiff, so sharp — when you take a step and the brain moves with respect to the device, you end up scrambling the tissue” — forming scars and leading to neuronal death surrounding the electrode.
Flexible fiber-based probes
Her team used novel fiber-fabrication technology pioneered by MIT professor of materials science (and paper co-author)Yoel Fink and his team.
The key to the new technology for neural probes is making a larger-scale version, called a preform, of the desired arrangement of channels within the fiber — optical waveguides to carry light, hollow tubes to carry drugs, and conductive electrodes to carry electrical signals. These polymer templates are then heated until they become soft, and drawn into a thin fiber, while retaining the exact arrangement of features within them.
Combining the different channels in a single fiber, she adds, could enable precision mapping of neural activity, and ultimately treatment of neurological disorders, which would not be possible with single-function neural probes.
For example, light could be transmitted through the optical channels to enable optogenetic neural stimulation. Its effects could then be monitored with embedded electrodes. At the same time, one or more drugs could be injected into the brain through the hollow channels, while electrical signals in the neurons are recorded to determine, in real time, exactly what effect the drugs are having.
MIT | Multifunctional fibers communicate with the brain
Customizable toolkit for neural engineering
The system can also be tailored for a specific research or therapeutic application by creating the exact combination of channels needed for that task. “You can have a really broad palette of devices,” Anikeeva says.
The fibers could ultimately be used for precision mapping of the responses of different regions of the brain or spinal cord, Anikeeva says, and ultimately may also lead to long-lasting devices for treatment of conditions such asParkinson’s disease.
John Rogers, a professor of materials science and engineering and of chemistry at the University of Illinois at Urbana-Champaign who was not involved in this research, says, “These authors describe a fascinating, diverse collection of multifunctional fibers, tailored for insertion into the brain where they can stimulate and record neural behaviors through electrical, optical, and fluidic means. The results significantly expand the toolkit of techniques that will be essential to our development of a basic understanding of brain function.”
The new technology is described in a paper appearing in the journal Nature Biotechnology, written by Anikeeva and 10 others. An earlier paper by the team described the use of similar technology for use in spinal cord research.
The work was supported by the National Science Foundation, the Center for Materials Science and Engineering, the Center for Sensorimotor Neural Engineering, the McGovern Institute for Brain Research, the U.S. Army Research Office through the Institute for Soldier Nanotechnologies, and the Simons Foundation.
MRI study has revealed that psychopathic violent offenders may be unable to learn from punishment due to the presence of abnormalities in their brains.
Frequent repeat offending among people with psychopathy suggests that punishment does not modify their behavior.
The study, published in Lancet Psychiatry, shows that abnormalities can be found in the areas of the brain associated with learning from punishment. These abnormalities were not found in the brains of non-psychopathic violent offenders or non-offenders.
“One in five violent offenders is a psychopath,” states study author Prof. Sheilagh Hodgins. “They have higher rates of recidivism and don’t benefit from rehabilitation programs. Our research reveals why this is and can hopefully improve childhood interventions to prevent violence and behavioral therapies to reduce recidivism.”
Researchers typically use the term “psychopath” to refer to individuals who display “moral depravity” or “moral insanity,” despite exhibiting outwardly normal behavior.
Dr. Nigel Blackwood, co-author of the study, explains that psychopathic offenders are different from regular criminal in a variety of ways. While regular criminals are respond to threat swiftly and are quick-tempered and aggressive, psychopaths have a low response level to threats, act cold and their aggression is premeditated.
“Evidence is now accumulating to show that both types of offenders present abnormal, but distinctive, brain development from a young age,” he adds. The identification of neural mechanisms in their brains behind persistent re-offending is key to the development of effective programs of rehabilitation and further crime prevention.
A comparison of brains
The researchers examined brain structure and functioning among a sample of violent offenders and healthy non-offenders in the UK utilizing magnetic resonance imaging (MRI).
From the British probation service, the team recruited 12 violent offenders with antisocial personality disorder and psychopathy and 20 violent offenders with antisocial personality but not psychopathy. Their brains were compared to those of 18 healthy non-offenders.
Among the participants with psychopathy, reductions in gray matter volume were found in the areas of the brain associated with empathy, moral reasoning and the processing of emotions such as embarrassment and guilt. The team also observed specific abnormalities that are associated with a lack of empathy considered typical of psychopathy.
While their brains were being scanned, participants completed an image-matching task designed to evaluate their ability to alter their behavior when they received positive or negative responses to their actions.
When previously rewarded responses were punished, the researchers observed that violent offenders with psychopathy displayed abnormal responses in certain areas of the brain in comparison with the non-offenders and the violent offenders without psychopathy.
“These results suggest the violent offenders with psychopathy are characterized by a distinctive organization of the brain network that is used to learn from punishment and from rewards,” says Dr. Blackwood.
Learning-based interventions could ‘significantly reduce violent crime’
Decision-making typically involves the weighing up of potential positive and negative outcomes of possible actions. Prof. Hodgins believes that offenders with psychopathy may only consider the positive consequences of their actions, failing to take account of any potential negative outcomes:
“Consequently, their behavior often leads to punishment rather than reward as they had expected. Punishment signals the necessity to change behavior. Clearly, in certain situations, offenders have difficulty learning from punishment to change their behavior.”
The findings of the study give new insight into the neural mechanics behind the actions of violent offenders with psychopathy. The difference observed by the team between violent offenders with antisocial personality disorder with and without psychopathy could influence future treatment programs for these conditions.
This research could also serve as a foundation for further research into the abnormal development of violent offenders, which Dr. Blackwood believes could be tested in studies of children.
“Since most violent crimes are committed by men who display conduct problems from a young age, learning-based interventions that target the specific brain mechanisms underlying this behavior pattern and thereby change the behavior would significantly reduce violent crime,” Prof. Hodgins suggests.
Their idea is to coax human pluripotent stem cells to become dermal papilla cells — a unique population of cells that regulate hair-follicle formation and growth cycle. (Human dermal papilla cells on their own are not suitable for hair transplants because they cannot be obtained in necessary amounts and rapidly lose their ability to induce hair-follicle formation in culture, the researchers explain.)
“Our stem cell method provides an unlimited source of cells from the patient for transplantation and isn’t limited by the availability of existing hair follicles,” Terskikh said.
“We developed a protocol to drive human pluripotent stem cells to differentiate into dermal papilla cells and confirmed their ability to induce hair growth when transplanted into mice.”
“Our next step is to transplant human dermal papilla cells derived from human pluripotent stem cells back into human subjects. We are currently seeking partnerships to implement this final step.”
In the U.S. alone, more than 40 million men and 21 million women are affected by hair loss, according to the researchers.
The research was published online in PLOS One (open access) Tuesday (Jan. 27). Terskikh was supported in the study by funds from Sanford Burnham Medical Research Institute, located in La Jolla, California and Orlando, Florida.
Wang, Zhang and others have experimented with different designs and fuel systems for micromotors that can travel in water, blood and other body fluids in the lab.
“But this is the first example of loading and releasing a cargo in vivo,” said Wang. “We thought it was the logical extension of the work we have done, to see if these motors might be able to swim in stomach acid.”
How it works
In the experiment, the mice ingested tiny drops of solution containing hundreds of the micromotors, which are 20 micrometers long. The motors become active as soon as they hit the stomach acid and zoom toward the stomach lining at a speed of 60 micrometers per second. They can self-propel like this for up to 10 minutes.
This propulsive burst improved how well the cone-shaped motors were able to penetrate and stick in the mucous layer covering the stomach wall, explained Zhang. “It’s the motor that can punch into this viscous layer and stay there, which is an advantage over more passive delivery systems,” he said.
The researchers found that nearly four times as many zinc micromotors found their way into the stomach lining compared with platinum-based micromotors, which don’t react with and can’t be fueled by stomach acid.
Wang said it may be possible to add navigation capabilities and other functions to the motors, to increase their targeting potential. Now that his team has demonstrated that the motors work in living animals, he noted, similar nanomachines soon may find a variety of applications including drug delivery, diagnostics, nanosurgery and biopsies of hard-to-reach tumors.
But is it safe?
The researchers explain that stomach acid reacts with the zinc body of the motors to generate a stream of hydrogen microbubbles that propel the motors forward. In their open-access study published in the journal ACS Nano, the researchers report that the motors lodged themselves firmly in the stomach lining of mice. As the zinc motors are dissolved by the acid, they disappear within a few days leaving no toxic chemical traces.
When they loaded up the motors with a test “payload” of gold nanoparticles, Wang, Zhang and their coworkers found that more of these particles reached the stomach lining when carried by the motors, compared to when the particles alone were swallowed. The motors delivered 168 nanograms of gold per gram of stomach tissue, compared to the 53.6 nanograms per gram that was delivered through the traditional oral route in the test.
“This initial work verifies that this motor can function in a real animal and is safe to use,” said Zhang.
JacobsSchoolNews | Stomach Acid-Powered Micromotors Get Their First Test in a Living Animal
Looking at US census data of 12,291 people, the researchers analysed their income, together with reports of how happy they were.
They discovered that people who were well-off didn’t necessarily become happier by having money, but when they had to deal with an emergency situation like having a leaking roof, with money in the bank they were much less sad than people on a lower income.
Lower incomes can lead to sadness
For people who couldn’t afford to pay for a leaking roof, experiencing sleepless nights worrying about being able to solve the problem could lead to sadness.
“Money may be a more effective tool for reducing sadness than enhancing happiness,” researchers Kostadin Kushlev, Elizabeth Dunn and Richard Lucas wrote in the paper.
The researchers say that happiness and sadness are two distinct emotional states, rather than being complete opposites.
“Although extensive previous research has explored the relationship between income and happiness, no large-scale research has ever examined the relationship between income and sadness,” the researchers wrote.
“We show that higher income is associated with experiencing less daily sadness, but has no bearing on daily happiness.”
These people achieve far more satisfaction from investing or saving their money than in spending it.
Other research published last year by Dunn, together with Michael Norton, an associate professor of marketing at Harvard Business School, found that people could be happier if they spent their cash on other people, rather than material possessions.
“Shifting from buying stuff to buying experiences, and from spending on yourself to spending on others, can have a dramatic impact on happiness,” Dunn and Norton wrote in the book Happy Money: The Science of Smarter Spending.
The researchers found that people who spent money on holidays gained more happiness from the experience rather than material goods. An increase in happiness was also seen in pre-paying in advance for an experience, as it allowed time for positive expectations to build up.