Science

It has long been common scientific knowledge that monkeys don’t realize that the reflection they see in the mirror is their own. But, according to new research by the Chinese Academy Sciences, monkeys can learn to recognize their reflections.

“Mirror self-recognition is an indication of self-awareness, which is a hallmark of higher intelligence in humans, as an indication of self-awareness. This ability may be acquired through training in monkeys,” Dr. Neng Gong of the Chinese Academy of Sciences, lead researcher of the study, told The Speaker. “Thus scientists can now study the neural circuit mechanisms underlying the emergence of self-awareness.”

Although humans and great apes have been found to recognize their reflections, rhesus monkeys had not. Over the course of decades of testing, rhesus monkeys failed to show any signs of self-recognition, such as touching and examining themselves while looking at the reflected image.

The monkeys could, however, use the mirrors as tools to observe other objects, previous studies showed.

The Chinese study tried a new approach and obtained new results. Rather than offering rhesus monkeys variously shaped and size mirrors as in past studies, Gong and his colleague taught the monkeys that a spot of irritating light shined on their faces was the same the monkeys saw in the mirror image.

The researchers spent 2 to 5 weeks training the monkeys by directing a laser light onto their faces while the monkeys sat in front of mirrors. The monkeys learned to touch the light spot on their faces that they could not feel–only see in the mirror.

The monkeys–or five out of seven, anyway–touched the light spots and also looked at and smelled their fingers after touching the light spot.

The monkeys also continued to explore using the mirror image to investigate parts of their bodies they didn’t normally see.

The researchers concluded that the monkeys had passed the test for mirror self-recognition.

“Our findings suggest that the monkey brain has the basic ‘hardware’ [for mirror self-recognition], but they need appropriate training to acquire the ‘software’ to achieve self-recognition,” the researchers stated of their work.

“In an evolutionary view, the ability of self-recognition seems not so important for monkeys, because they do not need this ability for living,” Gong told us. “However, for humans, self-awareness is the most important function for higher human-specific brain function for social behaviors, e.g., sympathy, empathy, perspective-taking (understand the situation by taking other’s perspective), and language communication. Understanding the neural basis of self-awareness and consciousness is the ultimate goal of understanding the human brain, and this has been a very difficult subject for experimental studies. By demonstrating that self-awareness-like behavior of mirror self-recognition can emerge in monkey after training, we now have an animal model to study what neural circuit changes that enable the emergence of self-awareness.”

The study is expected to shed new light on the neural basis of self-awareness among animals. It also is expected to hold hope for sufferers of diseases like Alzheiers, schizophrenia, autism and mental retardation, in which people are unable to recognize themselves in mirrors.

“Mirror neurons were first discovered in macaque monkeys and thought to be a mechanism for imitation behaviors,” Gong told us. “In human beings, it has been speculated that mirror neuron systems are the brain mechanism underlying self-awareness and empathy. It is possible that the ability of rhesus monkeys in acquiring mirror self-recognition depends on their possession of mirror neuron systems.

“Our study raises the possibility that monkeys can be used as an animal model to test this hypothesis. This calls for further brain imaging and neural circuit analysis of the changes in the monkey’s brain before and after training of visual-somatosensory association and in those monkeys that passed or failed the mark tests after training.

“Indeed, we have already started further mechanism studies.”

The report, “Mirror-induced self-directed behaviors in rhesus monkeys after visual-somatosensory training,” was authored by Neng Gong and was published in Current Biology.

Photos: Neng Gong and colleagues/Current Biology 2015

 

As part of a larger body of work to explore “the Science of Intellectual Humility,” a joint-research team has investigated the differences between two types of humility. The two types are each characterized by a cluster of traits: general humility by social traits, and intellectual humility by a composite of traits that add up to a love of learning.

“We were happy to discover that intellectual humility seems to be a concept that has its own place in the minds of the general population distinct from general humility,” Peter Samuelson, post-doctoral researcher in psychology at Fuller Theological Seminary and lead study author, told The Speaker about the work.

“By the same token, there are many shared characteristics between an generally humble person and an intellectually humble person in the folk conception (such as modesty) which we expected. What surprised us from the study was that intellectual humility is distinctly tied together with love of learning, curiosity, and a desire to seek the truth. These were not words used to describe a wise person and seem unique characteristics of an intellectually humble person in the folk mind.”

The research team undertook a bottom-up study of the meaning of humility, and found two clusters of traits associated with humility in the minds of participants. One type of humility, called “socially humble,” included traits like sincerity, honesty, unselfishness, thoughtfulness and maturity. The other type, called “intellectually humble,” had to do with a love of learning. Curious, bright, logical and aware were among the traits in this cluster.

Samuelson explained the distinction between general and intellectual humility, which can lead to a greater desire to learn new things from other people.

“While we did not test the difference between intellectual and general humility in the folk understanding (we compared ideas the general public had of an intellectually humble person, a wise person, and an intellectually arrogant person), the main distinction is that intellectual humility uniquely impacts how a person learns and acquires new knowledge.

“While characteristics of general humility may help a person be willing to learn from others and open to new knowledge, the unique characteristics of intellectual humility–such as an understanding of the limits of one’s knowledge, a search for the truth, a love of learning, among others–can motivate learning beyond what general humility can. It should be no surprise that the ‘intellectual’ aspects of intellectual humility are what make it distinct from general humility and that some of the social aspects (modesty, not bragging, being considerate, being friendly) are shared between the two forms of humility in the folk mind.”

Samuelson explained how a greater understanding of what constitutes intellectual humility could lead to improvements in people’s lives–in particular, he commented on a need to benefit from each others’ differences in a time when people have the option to tune out those who disagree.

“According to the understanding held by the broadly representative sample of the general population we surveyed–cultivating the virtue of intellectual humility could help enhance a lifelong love of learning and could bolster curiosity and truth seeking, as well as help people be open to engaging others in those endeavors and thereby promote a more collaborative and civil search for truth.

“These qualities are sorely needed in an era when in every sector of our society people seem quite sure they are right and those who disagree with them are wrong (intellectual arrogance), who seem to want to listen to people who will only confirm what they already know. Developing the virtue of intellectual humility will not only help us learn, but also help us collaborate and learn from each other, and could move the needle toward more civil discourse in our society and ultimately finding the best solutions to our intractable problems.”

The report, “Implicit theories of intellectual virtues and vices: A focus on intellectual humility,” was completed by Peter L. Samuelson, Matthew J. Jarvinen, Thomas B. Paulus, Ian M. Church, Sam A. Hardy, Justin L. Barrett, and was published in the Journal of Positive Psychology. The research is part of a larger grant from the John Templeton Foundation to study “the Science of Intellectual Humility,” and was housed at the Thrive Center for Human Development at Fuller School of Psychology in Pasadena, CA.

The complete genome for the bowhead whale has been mapped and the results have been presented by University of Liverpool researchers. The researchers expect that the research help build an understanding of “tricks of biology” that the species–which lives up to 200 years with low incidence of age-related diseases–have developed to increase their lifespans.

“My view is that species evolved different ‘tricks’ to have a longer lifespan, and by discovering the ‘tricks’ used by the bowhead we may be able to apply those findings to humans in order to fight age-related diseases,” Senior author Dr. João Pedro de Magalhães, of the University of Liverpool, in the UK, said of the research.

“Our understanding of species’ differences in longevity is very poor, and thus our findings provide novel candidate genes for future studies.”

The bowhead genome is the first to be sequenced among large whales. The researchers included in the presentation of their findings the identification of key genetic differences from other mammals, including genes related to cell division, DNA repair, cancer and aging.

The new genome map carries hope that physiological adaptations related to the whale’s massive size will become understood, such as the relatively low metabolic rate possessed by the large mammals. The team identified one particular gene–UCP1, which plays a role in thermoregulation–that they suspect may be important in this regard.

Read more: “Tricks” of major puzzle of biology sought in longest lived mammal

The researchers remarked that the bowhead not only lives long, but lives disease-free until an age much more advanced than that at which humans frequently begin to become burdened by illnesses.

Magalhaes also noted that large whales have over 1000 times the number of cells humans have, yet the large mammals do not seem to suffer from increased cancer risks associated with the massive amount of cells. Magalhaes suspects that this points to natural mechanisms possessed by the whales genes that more effectively suppress cancer.

Next for the team is a project to breed mice to express some of the standout bowhead genes. They hope to find genes for longevity and disease resistance.

The report, “Insights into the evolution of longevity from the bowhead whale genome,” was authored by Dr. João Pedro de Magalhães and was published in the journal Cell Reports.

Information on the research can also be found at the team’s genome resource webpage.

In a first-of-its-kind study undertaken by University of California researchers, elite bargainers–those responsible for making today’s most important policy and business decisions–were examined to find out if they, like other people, reject low offers even when those offers involve benefits. The research is expected to offer increased understanding of some of the problems faced in global economic and environmental dialogues.

“Professionals, who had a lot of experience in high-stakes bargaining, played even further from the predictions of classic economic models. Concerns about fairness and equity aren’t expunged by experience, and persist in a group of very smart and successful professionals,” Dr. Brad LeVeck, Assistant Professor at the University of California, Merced, and lead author of the study, told The Speaker.

“Most experiments in human behavior are conducted on convenience samples of university undergraduates. So, when experimental results go against the assumptions in classic models from economics, many researchers are skeptical about whether those results will translate to the real world,” LeVeck told us.

“Inexperienced students at a university might just be making mistakes that more experienced professionals would avoid. At least when it comes to bargaining, our study shows that this isn’t the case.”

LeVeck’s study used a unique sample of 102 US policy and business elites who had an average of 21 years of experience conducting international diplomacy or policy strategy.

The names of the participating elites were withheld in order to mitigate possible false behavior that could have resulted from concern about harm to their reputations.

When participants bargained over a fixed resource–in the study the samples played “ultimatum” bargaining games that involved the division of a fixed prize, but the researchers had global agreements on international trade, climate change, and other important problems in mind–the elites actually made higher demands and refused low offers (below 25 percent in the share of a prize) more frequently than non elite bargainers. But elite bargainers also offered more.

“In our study, it wasn’t just the case that elite policy makers rejected low offers more often than the general public,” LeVeck said. “It was also the case that they made more generous offers.

“So, to a certain extent, these individuals have the right intuition about how to conclude a successful bargain. This suggests that considerations of equity and fairness are already taken into consideration by real world policy makers.”

Elites with more experience and age were found to bargain for higher gains all around.

“Our best evidence indicates that this finding is related to their professional experience… This could be because policy makers accommodate the possibility that low offers will be rejected, and therefore also learn that it’s generally ok to reject low offers.”

The positions from which the most important policy and business decisions are made, the researchers concluded, are occupied by elites who have either changed towards high demand bargaining or have been selected by some process that favors this type of elite.

Why bargainers reject low offers and why elite bargainers play for higher stakes are questions that are still unanswered. Past research has given weight to arguments that bargaining actions are not due to motives such as fairness, equity, or toughness, but may have more to do with spite, culture and social learning.

“Our study wasn’t designed to disentangle these explanations,” LeVeck said. “So, it’s difficult to know whether the people who reject low offers are individuals that intrinsically care about fairness for everyone, or are simply individuals who spitefully reject low offers (but would take more for themselves if it were possible). In the later case, people would care about fairness for themselves, but not for everyone. I suspect both of these motivations exist and affect the behavior of different people.”

The researchers considered other motives for elite bargaining tactics, such as future opportunities, other bargaining partners and power relationships, but those did not play into the experiments.

“I do think these types of complex, real-world considerations shape professionals’ intuitions about how to bargain,” said LeVeck. “However, other parts of our study show that policy and business elites think carefully about strategic decisions. This makes it less likely that these individuals were misapplying a lesson from the real world when they played the bargaining game in our study.”

The researchers pointed out that the study encourages a reappraisal of aspects of international cooperation, such as bargaining with regards to trade, climate and other world issues.

“Analysts and researchers are understandably skeptical when leaders complain that an agreement is unfair. It’s very plausible that the complaint is just ‘cheap-talk’: When pressed, those leaders should actually accept any agreement that is inline with their self-interest.

“By contrast, our findings raises the possibility that these complaints are more than cheap talk. Policy and business elites have some willingness to reject inequitable offers.

“So, when formulating proposals on issues like global emissions reductions or trade policy, leaders should pay attention to whether the other side will reasonably regard the deal as fair.”

The report, “The role of self-interest in elite bargaining,” was completed by Brad L. LeVeck, D. Alex Hughes, James H. Fowler, Emilie Hafner-Burton, and David G. Victor, and was published on the PNAS website.

By Sid Douglas

Light has been shed on the longstanding question of how cells regulate size and how they know when to divide. According to recent research at UC San Diego, some cells–billions of years divergent from each other–use a unique, robust and simple method that had not been observed by scientists. The research has ruled out both of the prevailing theories of cell division–the so-called “timer” and “sizer” theories. Instead, evidence points towards an “adder” paradigm that corrects for differences in birth size through reproduction.

“Our experimental data and analysis of growth of Escherichia coli and Bacillus subtilis shows neither timer nor sizer are correct models,” Dr. Sattar Taheri, postdoctoral fellow in the Jun Lab in the Physics Department of the University of California, San Diego and first author of the report, told The Speaker. “Instead, cells ‘add’ a constant mass in since birth until division. That is, irrespective of the cell size at birth, cell grow by a constant size and then divide. This strategy automatically ensures that cell of larger/smaller than average size, correct their size within several generation.”

The new “adder” paradigm is a simple mathematical principle. Further mathematical model developed by the researchers helped understand fluctuations and distributions of cells’ growth parameters.

Read more: What causes cell division? Neither of the prevailing theories, but rather an extraordinarily simple quantitative principle of cell-size control, according to UC San Diego scientists

Time and size do not even factor into growth and division for “perfect adders.”

Taheri explained the problem approached by the research.

“In their life cycle, bacteria grow in size until they divide into two daughter cells. Scientists knew that cells have a ‘strategy’ to control their size–or, in other words, when to divide–but we did not know what that strategy is.

“In fact, this has been one of the long standing problems in biology.”

The research was conducted with a device that allowed the team to isolate individual genetic materials and observe the E. coli and B subtilus over hundreds of generations and under various conditions. Samples about a thousand times better than previous samples were derived from this process.

“Without a powerful technology to precisely acquire data on growth of live cells, people could only suggest theories. ‘Timer’ and ‘sizers’ were two major ideas. Based on the timer model, cells have a clock. The clock start when cells are born, and once a constant period of time passes, division is triggered–irrespective of the cell size. The sizer model suggests that growing cells divide once they reach a critical size. This requires cells continuously monitor their size.

The research, as Taheri stated, found that the previously posed models could not explain growth and division. Instead, a surprising new concept emerged: the “adder” paradigm that applied to most of the bacteria the team has so far studied–as well as the data coming out of other labs.

However, the solution is only a part of a greater picture. Taheri noted that cell division was much more complex than a single theory could explain.

In particular, higher organisms “care more” about size, and add more mass before dividing if they are born smaller. That said, those cells also reach target size in the same way that perfect adders do, according to the researchers.

“Note that this adder principle is not the only possible strategy to maintain size homeostasis. It was unexpected to find this, specially in both E. coli and B. subtilis–that are billion years apart in evolution. It’s a unique way. Robust and simple. However, some other higher organisms, including yeast, seems to use other strategies.”

The two reports that resulted from the research, “Cell-size maintenance: universal strategy revealed” and “‘Cell-size control and homeostasis in bacteria” were completed by Suckjoon Jun, Massimo Vergassola and Sattar Taheri-Araghi, and were published in the journal Current Biology. Both papers will be available at the Jun Lab webpage.

According to new psychology research, personality is at least as important as intelligence when it comes to school. Some personality traits are more important than others, according to the findings, and the study has led researcher Dr. Arthur Poropat of Griffith’s School of Applied Psychology to suggest that educators may do better to target the fluid, teachable capacities of personality rather than rely on the more static capacity of intelligence alone.

“Personality is at least, if not more important than intelligence for education,” Poropat told The Speaker. “And unlike intelligence, we can help people to develop their personality to improve their academic performance and life outcomes.”

Poropat conducted the largest ever reviews of personality and academic performance based on the five fundamental personality factors–Conscientiousness, Openness, Agreeableness, Emotional Stability, and Extraversion. He found that Conscientiousness and Openness have the biggest influence on academic success, and helpfulness was found to also be involved in scoring grades.

“Students who scored highest on the three most relevant personality factors scored a full grade higher than students who scored lowest on those factors. The three factors are: Conscientiousness, which reflects things like making and carrying out plans, striving to achieve, and self-control; Openness (also called Openness to Experience and Intellect), encompassing being imaginative, curious, and artistic; and Emotional Stability, covering calmness and emotional adjustment (as opposed to being anxious, fearful or unstable). The two personality factors that are not so strongly linked with academic performance are Agreeableness (reflecting likability and friendliness), and Extraversion (talkative and socially-dominant).

“What my reviews of the research on personality and academic performance found was that Conscientiousness is at the very least just as important as intelligence for predicting academic performance.”

Who was doing the assessing was also a matter of the research. A students self-assessment was found to be as useful as a predictor of success in university as intelligence rankings, but the assessments of other students–those who knew the individual in question well–were found to be much more accurate than either.

“If someone who knows the student well rates the student’s personality, Conscientiousness is nearly four times as important.

“So, students who habitually manage their effort, make and stick to plans, and stay motivated regardless of set-backs, do substantially better, and this is more important than how smart the student is. Likewise, both Openness and Emotional Stability are much more useful for predicting grades and GPA when rated by someone who knows the student well. In other words, the creative and intellectually-curious students, and the calm and emotionally well-adjusted students, will do better at school and university.”

In general, personality was found to be more important than intelligence when it came to academic careers. Poropat explained why this might be.

“One way of thinking about this is that intelligence is a bit like horsepower for a car: it gives a student their basic capacity to learn. Conscientiousness, Openness and Emotional Stability is more like the way in which the car is driven. With respect to cars, a great driver in an average car will outperform a bad driver in a great car. Similarly, a student with average intelligence but who is high on Conscientiousness, Openness, and Emotional Stability will outperform an intelligent student who scores lowly on these factors.”

Poropat commented on some changes that could be made to education to improve its benefits to students.

“One thing that surprised me when I completed the first of my studies was that teachers already ‘knew’ what the results were. The many teachers I have spoken with typically say that hard-working, intellectually curious, and well-adjusted students perform better than smart students, in part because they are easier to teach. However, there is clear evidence from independent research–i.e., not mine–that students can be taught to change their personality in ways that help their studies. What I would like to see is education actively targeting personality development in ways that are closely linked to study and work. We already know this is possible and it produces good outcomes for students but we need more attention to this, and more research on how best to achieve this. Some of my postgraduate research students are already exploring this area.”

Not only can good personalities be taught to some degree, but students may be setting themselves up for failure by depending on the static capacity of intelligence, which is different from the fluid capacity of personality, according to Poropat.

“Professor Carol Dweck has done a lot of research on why teachers and parents should never tell a student they have done well because they are smart,” he explained. “The reason is that the students seem to know what research tells us: despite the mind-training software, it seems that it is not possible to truly improve someone’s intelligence. So, if a student thinks they have done well because they are smart, they conclude there is no point in making an effort so they stop trying and their performance gets worse.

“However, there is clear evidence that personality does change over time, and that it is possible to train people to change their personality–at least as far as changing how they consistently behave. In contrast with intelligence, students seem to know that they can learn new ways of managing themselves, and new ways of exploring ideas and skills, and new ways of managing their emotions. People typically develop higher levels of Conscientiousness with age, but they can also be taught this. And, people can also be taught to be higher on Openness and Emotional Stability. So, students of any age can develop their personality to improve their academic performance: the challenge is for educators to show them how.”

Poropat concluded that much of classroom success depends on how teachers bring out the best in students.

“Teachers need to help students develop their personalities in constructive ways. That is because, unlike intelligence, teachers can guide students to be more conscientious, open to experience, and emotionally-stable, which are the three personality factors that have the biggest effect on whether students learn well. Teachers should pay attention to whether students’ personalities support learning, and use that to guide teaching of individual students.

The report, “Other-rated personality and academic performance: Evidence and implications,” was completed by Arthur E. Poropat, and was published in the journal Learning and Individual Differences.

How small are Dr. Pedro A. Quinto-Su’s steam engines? Smaller than red blood cells and most bacteria–between one and three millionths of a meter. The significantly strong pistons are powered by a combined process of optical manipulation which bypasses microfabrication and draws strength from simplicity, taking scientists one step closer to the “lab on a chip” miniaturization of everything.

“The piston–a microsphere–is powered by light, which also heats the sphere inducing the vapor microexplosions. Similar to an internal piston combustion engine,” Dr. Pedro Quinto-Su, physics professor at the Universidad Nacional in Mexico, told The Speaker.

“This is the first time that a steam engine has been miniaturized to a length scale of a micrometer,” Quinto-Su told us. “Also, the engine works in an environment dominated by fluctuations (Brownian), since it is immersed in liquid. In the context of optical micromanipulation the report shows that it is possible to have impulsive forces in an optical tweezer, which could extend even more the wide array of applications that use that technique.”

Quinto-Su placed the microscopic piston in historical context.

“In the past, the improved steam engine design of Watt started the industrial revolution and understanding the mechanism initiated modern thermodynamics. Steam engines were the foundation for all the engines that we have today.

“Now steam engines are mainly used for energy conversion in power plants, where steam turbines convert mechanical energy into electricity.”

There has been much interest in miniaturizing heat engines, Quinto-Su explained.

“In the last few decades there has been a trend in trying to miniaturize everything. In science this concept has been called “lab on a chip” and the idea is to have everything that is needed to make an experiment in a small chip. The interest in miniaturized versions of heat engines is that they could be used to do work in very localized volumes. For example, periodically displacing small objects including nanomaterials.”

Quinto-Su explained the challenges to miniaturization past the 1mm scale–the lower limit until the recent invention–and how his steam engine bypassed the previous obstacles.

“The main problem with tiny heat engines is that the efficiency is very poor. A few heat engines have been demonstrated at the micrometer scale with different working mechanisms. However, traditional heat engines that work with the expansion and compression of gas had not reached scales below 1mm, perhaps because most designs involved the assembly of microfabricated moving parts which made it more challenging–in addition to the expected poor efficiency.

“The implementation of the reported micrometer-sized piston steam engine is very simple and there is no need for microfabrication, only optical access is required. It needs an optical tweezer setup which is a widely available tool.”

Quinto-Su explained how the project began–as an attempt to combine two methods of microscopic manipulation to create the micro-piston.

“The project started by trying to combine two techniques of optical manipulation of microscopic objects immersed in liquids: optical tweezers and microscopic explosions (cavitation bubbles).”

Quinto-Su explained how small the steam engines were, and put in layman’s’ terms  how the various elements of the engines work.

“In the reported engine a spherical microparticle (1 or 3 micrometers in diameter, the largest dimension of a human red blood cell is about 10 micrometers) is periodically displaced by light and microscopic explosions.

“Optical tweezers use a focused laser beam that attracts transparent microscopic objects towards the focused spot. The objects are usually immersed in liquid and they are called colloids, usually these objects are microscopic spheres. Once the microparticles reach the focus of the laser beam they stay trapped in there. This technique exerts very small controlled forces (pico Newtons) in the microscopic objects.

“In contrast, microscopic vapor explosions in liquids exert large impulsive forces in the vicinity where the explosions are created. A vapor explosion creates a rapidly expanding bubble that later collapses (cavitation bubble). The bubble displaces the liquid at a very fast speed which also displaces the objects in the vicinity, exerting impulsive forces several orders of magnitude larger than those of optical tweezers.

“In the reported work, a spherical microparticle that is not completely transparent to the laser beam is placed in an optical tweezer. In this way the sphere is attracted towards the focus of the beam, but at the same time it is heated because it is not transparent to the light. Once the sphere is close to the focus it is heated at a very fast rate and the liquid in contact with the microsphere explodes, pushing the sphere close to the starting position. Then the light forces take over and start attracting the sphere towards the focus repeating the cycle.

“Hence the combination of optical tweezers and vapor explosions resulted in a microparticle (piston) that is periodically attracted towards the focused laser and then is pushed away at a fast speed by microscopic vapor explosions. In a sense it is similar to an internal piston combustion engine.”

Quinto-Su noted that the the microexplosions are not initiated by a spark, but by a sudden temperature increase, similar to a diesel engine.

The power created by the pistons is significant, Quinto-Su explained.

“The average power is about 0.3 pico Watts and the power density is about two orders of magnitude less than that typical of car engines. However the effects at the microscopic scale are significant and could be used to pump small volumes of liquid or exert impulsive forces in nearby objects.”

The micro-pistons can be compared with the effect of transducers when driven at acoustic and ultrasound frequencies.

“Because transducers can be used to induce oscillations in liquid-gas boundaries which produce flow. In this case, the operation of the engine is periodic displacements of the piston and periodic explosions which also produce flow, similar to the effect of transducers.”

The report, “A microscopic steam engine implemented in an optical tweezer,” was authored by Pedro A. Quinto-Su and was published in Nature Communications

Three videos from Dr Pedro A. Quinto-Su’s research – 1-3 μm particle engines.

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Does the entire library of memories stored throughout our lifetime remain dormant within our minds, and can these memories be restored? New research has led UCLA neurobiologists to conclude that the storage mechanism for memories is actually independent of synaptic change–the mechanism that mediates the expression of memories. Rather, memories are stored in persistent epigenetic changes within the nuclei of neurons, and therefore memories are extremely stable over time and could be restored.

“The idea, long believed by most neuroscientists, that memories are stored in synapses may be incorrect. This implies that the apparent loss of a memory due to synaptic elimination might be reversible. Memories that appear to be lost forever may, in fact, be able to be fully restored,” Dr. David Glanzman, professor of integrative biology, physiology and neurobiology at UCLA and lead author of the study, told The Speaker.

So if the memories remain stored intact, why can’t we access them? The synapses that complete the circuit to the memories are destroyed or eliminated, Glanzman suspects. Glanzman qualified that the problem of memory storage was extremely complex and that he did not possess a complete answer, but he explained how his conception of memory formation was changed by the research.

“At present I believe that memories are formed in the brain by a combination of posttranslational changes—protein phosphorylation, protein dephosphorylation, etc.—gene transcription, protein synthesis and structural changes in neurons.  Pretty much everyone in the field of learning and memory also believes this.

“Where I differ is that I now believe that the storage mechanism for long-term memories is independent from the mechanism that mediates the expression of the memories, which is synaptic change,” Glanzman continued. “The storage mechanism, I believe, is persistent epigenetic changes within the nuclei of neurons.  Given this, I think that long-term memories are actually extremely stable; as long as the cell bodies of the neuronal circuit that contains the memory are intact, the memory will persist.  The memory can appear to be disrupted, however, by destroying or eliminating the synapses among the neurons in the neuronal circuit that retains the memory.  But the apparent elimination of a memory due to synaptic elimination can be reversed and the memory restored.  The data in our eLife study support this idea, although they do not explain how this is actually accomplished.”

In their research, the UCLA team studied Aplysia, a marine snail–particularly the way Aplysia learns to fear a memorable source of harm.

The team trained the snail to defend itself by withdrawing to protect its gills from the harm of mild electric shocks. The snail retained the withdrawal response for several days, indicating long term memory of the stimulus.

The team found that the shock caused serotonin to be released in Aplysia’s central nervous system. New synaptic connections grow as a result of the serotonin, according to the team. The formation of memories can be disrupted by interfering with the synthesis of the proteins that contribute to the new synapses.

When a snail was trained on a task but its ability to immediately produce the proteins was inhibited, the animal would not remember the training 24 hours later, the researchers found, but if an animal was trained and protein synthesis was inhibited later–after 24 hours–the animal would retain the memory. Memories once formed last in long-term memory, the team found.

They also performed experiments with neurons in a Petri dish, and found the same results.

Then the team tested memory loss. Again in a Petri dish, they manipulated synaptic growth with a protein synthesis inhibitor and with serotonin. They found that when they stimulated synaptic growth some time after creating a memory, new synapses grew–not the old ones that would have been stimulated if prevailing theories of memory formation were accurate.

The researchers found that the nervous system appears to be able to regenerate lost synaptic connections–reconnecting memories with new synapses.

Does that meant that the entire library of a life’s memories could be dormant and could be restored? Possibly, but not in all cases, according to the study. Glanzman used an example to explain what his research had suggested.

“That is a fascinating question,” said Glanzman.”For example, what about the phenomenon of infantile amnesia, that is, the inability of adults to retrieve episodic memories before the age of 2–4 years?  Can those episodic memories from our earliest years be restored?  I frankly don’t know, but I suspect that they can be.  It is possible that the explanation for infantile amnesia is similar to that of the phenomenon we examined in our study, reconsolidation blockade.  There, we found that the apparent elimination of the memory was the result of the reversal of the synaptic growth and, perhaps, of some of the epigenetic changes, such as histone acetylation, that mediated the expression of the memory.

“Notice that some epigenetic changes are intrinsically more stable than others.

“What if infantile amnesia is also a consequence of synaptic loss and reversible epigenetic changes, but that the memory persists as persistent epigenetic changes?  Then, just as we were able to restore memory in the snail following its disappearance due to reconsolidation blockade, we might be able to reverse infantile amnesia.  Similarly, some memories lost in the early stages of Alzheimer’s disease due to the synaptic destruction might be restorable.  However, once the cell bodies of the neurons that make up the memory circuit die, I believe the memory is lost forever.”

Before the recent research, memory was believed to be stored in synapses. Glanzman explained the traditional belief and the remaining challenges to the new theory.

“First, until my work is confirmed by others, it is not fair to say that neuroscientists are mistaken in their belief that long-term memory is stored at synapses.  The idea that memory is not stored at synapses is going to be met with a great deal of skepticism, as any radical new scientific idea should be.

“Having said that, the idea that memory is stored at synapses grew out of the pioneering work of the Spanish neuroanatomist Ramon y Cajal (who was awarded the Nobel Prize in 1906).  Cajal was one of the first to propose that learning and memory involves the growth of new synaptic connections among neurons in the brain.  This idea is now overwhelmingly accepted by neuroscientists.  I certainly believe—and scientific research on Aplysia and other animals confirms—that when an animal learns, synapses in its brain (or nervous system, in the case of the snail) physically change; in some instances the result is synaptic growth, whereas in others it is synaptic retraction.  (The specific pattern of synaptic change depends on the specific type of learning and the particular part of the brain that mediates the learning.)

“Given this, it is natural to think that new memories will be stored, at least in part, as persistent molecular or structural changes in the synapses that grew as the memories formed. It is this part of the synaptic hypothesis of long-term memory that I disagree with.”

The research is expected to hold new hope for sufferers of Alzheimers. Because in the early stages of the disease, synapses are destroyed–not neurons–those memories still exist and could be regained, Glanzman suspects.

The report, “Reinstatement of long-term memory following erasure of its behavioral and synaptic expression in Aplysia,” was completed by Shanping Chen, Diancai Cai, Kaycey Pearce, Philip Y W Sun, Adam C Roberts, and David L Glanzman, and was publied in eLife.

Photos: Christelle Nahas/UCLA

How do cells control their size? What causes them to divide? Contrary to what many biologists have expected, evidence supporting an answer to one of the most fundamental and longstanding problems of biology has been accomplished by UC San Diego researchers. The study surprised even the researchers: a simple quantitative principle explains the phenomena without regard for either of the currently prevailing theories.

“Life is very robust and ‘plastic,’ much more than what biology textbooks tell us. Bacteria probably do not care when they should start replicating their genomes or dividing,” Dr. Suckjoon Jun, assistant professor of physics and molecular biology at the University of California, San Diego and one of the lead authors of the study, told The Speaker.

“Simple mathematical principles help us understand fundamental biology, just like in physics.”

How do cells control their size? What causes them to divide?

Biologists had previously posited two possible solutions: either a cell reaches a certain size, at which it divides into two smaller cells; or after a certain time has passed, the cell divides. The two theories have been known as “sizer” and “timer.”

The results surprised the researchers as well: “adder.”

“The results were completely unexpected,” Jun told us.

Rather than either sizer or timer paradigms, cells were found to add a constant volume each generation, regardless of their newborn size.

“This ‘adder’ principle quantitatively explains experimental data at both the population and single-cell levels, including the origin and the hierarchy of variability in the size-control mechanisms and how cells maintain size homeostasis,” the researchers concluded, whereas in past research based on “sizer” and “timer” theories led to difficult-to-verify assumptions or population-averaged data and varied interpretations.

Time and size, while variable in some organisms, do not even factor into the existence of “perfect adders” in the newly found and “extraordinarily simple” quantitative principle of cell-size control.

“It seems most bacteria we have studied so far, and more data is coming out of other labs, appear to be perfect adder,” said Jun. “Some higher organisms, such as yeast, do care about size more than bacteria do. For example, small-born yeast cells add more mass than large-born cells to reach division. That is, how much mass they add since birth is sensitive to how big the baby cell was. Nevertheless, the way they reach the target size, generation after generation, works exactly same as the perfect adders such as bacteria, which is quite nice and surprising.”

The growth of cells follow the growth law, the researchers found, and grow exponentially at a constant rate.

Jun explained the challenge that had stood in the way of understanding this aspect of cell division in the past: “Two biggest obstacles have been (one) dogmas that cells somehow must actively sense space or time to control cell size, and (two) technology that did not exist until recently, which now allows monitoring the growth and division patterns of tens of thousands of individual cells under tightly controlled environment.”

The research team developed a tiny device that isolates individual genetic materials.

The tool allowed the researchers to observe thousands of individual bacterial cells–Gram-negative E. coli and Gram-positive B. subtilis–over hundreds of generations. The researchers manipulated the conditions in which the cells lived. A wide range of tightly controlled steady-state growth conditions were experimented with.

According to the researchers, the new method allowed them to produce statistical samples about a thousand times better than had previosly been available.

“We looked at the growth patterns of the cells very very carefully, and realized that there is something really special about the way the cells control their size,” explained Jun.

“No one has been able to answer this question,” Jun said in their press release, noting that this was even the case for the E. coli bacterium, possibly the most extensively studied organism to date.

The research holds the promise of better informing the fight against cancer, since one of the most important problems in the fight is the process of runaway cell division.

The reports, “Cell-size maintenance: universal strategy revealed” and “‘Cell-size control and homeostasis in bacteria” were completed by Suckjoon Jun, Massimp Vergassola and Sattar Taheri-Araghi, and were published in the journal Current Biology .

Images: the work of the researchers

The share of farmland tended by small farmers is shrinking. The land is changing hands. Although small farms are more productive than large farms and tend to grow food products–they produce 80 percent of the world’s food–they are being swallowed up by large corporate farms that grow high-profit crops for export markets. The land left to the largely food-producing small farms is currently only 24 percent of fertile land, and that number is declining sharply.

“Over the past decades, small farmers have been losing access to land at an incredible speed,” Henk Hobbelink, coordinator of GRAIN, told The Speaker. “If we don’t reverse this trend we will not only have more hungry farmers in the future, but the world as a whole will lose the capacity to feed itself.”

GRAIN investigated land use data worldwide to understand the global and specific trends currently taking place with regard to farmland.

“What became very clear from our research is that increasingly fertile farmland is being taken over by huge industrial operations that produce commodities for the global market, not food for people,” Hobbelink told us. “Small farmers, who continue to produce most of the food in the world, are being pushed into an ever diminishing share of the world’s farmland.

“This trend has to be reversed if we want to be able to feed a growing population,” he said.

However, many governments and international organizations are offering grossly incorrect or misleading figures, according to GRAIN, such as those announced by representative’s of the UN Food and Agriculture Organization’s (FAO) recent “State of Food and Agriculture“–which was dedicated to family farming.

At this year’s inauguration of the International Year of Family Farming, UN FAO Director General Jose Graziano da Silva stated that 70 percent of the world’s farmland was managed by families, echoing previous conclusions by the UN and other world organizations.

The percentage of farm land currently in the hands of small farms (an average of 2.2 hectares) is, according to GRAIN, actually less than 25 percent. Excluding China and India–where about half of all small farms are located–the ratio is less than one-fifth.

Similar findings were in evidence for every region of the world.

For example, in Belarus small farmers produced over 80 percent of fruits, vegetables, potatoes and vegetables with only 17 percent of the land. In Botswana, small farmers produced at least 90 percent of millet, maize and groundnuts with less than eight percent of the land.

“Because rural peoples’ access to land is under attack everywhere. From Honduras to Kenya and from Palestine to the Philippines, people are being dislodged from their farms and villages,” GRAIN found. “Those who resist are being jailed or killed. Widespread agrarian strikes in Colombia, protests by community leaders in Madagascar, nationwide marches by landless folk in India, occupations in Andalusia–the list of actions and struggles goes on and on.”

Eighty percent is also the figure given for the percentage of the world’s hungry people who live in rural areas. Many of these people are farmers or farmworkers.

Hobbelink explained this finding to us by saying that it was the result of small farmers simply not having enough land to produce food, and losing access to land at a rapid rate.

There were six general findings GRAIN found to be most compelling.

First, most of the world’s farms are shrinking. Second, the total of these farms account for less than 25 percent of the world’s farmland. Third, big farms are getting bigger, and small farms and farmers are losing to them. Fourth, despite this, small farms continue to be the world’s biggest food producers. Fifth, overall, small farms are more productive than big farms. Sixth, most small farmers are women.

Particularly surprising to the researchers was that land was becoming increasingly concentrated, despite extensive global agrarian reforms.

A “kind of reverse agrarian reform” is taking place in many countries, according to GRAIN. Most of this is happening through corporate land grabbing in Africa and foreign investment and massive farm expansion in Latin America and Asia.

Besides land concentration, among the forces causing small farms to collapse are population pressure and lack of access to land.

Even in India and Asia farms have been shrinking. In India, the size of the average farm is 50 percent of what it was in the 1970s, and in China farm sizes shrunk 25 percent between 1985 and 2000.

In Africa, where no official statistics for farmland concentration were available to GRAIN, researchers based their conclusions on research papers that indicated small farms were shrinking there as well.

Why small farms produce so much, and why they are losing to big corporate farms, was explained by GRAIN in their report: small farms tend to focus on food production, which is then bought from local markets and eaten. Large farms focus on return on investment, and tend to grow more export commodities such as animal feed, biofuels, and wood products. Thus, big farms, with maximized profits, are able to buy more land to produce high-profit commodities.

“Corporate farms a backed by big money, often from the finance industry, investment firms, etc.,” Hobbelink told us. “They are also able to access and influence political decisions at high level, and in this way often get handed over huge swaths of land at incredible low prices or for free. In the meanwhile, small farmers don’t have access to credit, and are up against agricultural policies that discriminate against them.”

Besides that, however, small farms tend to be more productive than large farms anyway, according to GRAIN. This phenomenon, which has been termed “the productivity paradox” because it seems contrary to what many people are told, is evinced in statistics. In nine EU countries, small farms have at least double the productivity of large farms, and the other countries show only slightly higher productivity for large farms. According to their findings, GRAIN calculated that if large farms in some Central American and African nations were as productive as small farms, national agricultural production would double.

In its findings, GRAIN also pointed out that big farms are less productive even with more resource consumption, the best land, most of the irrigation water, and better credit and technical assistance.

Much of the disparity is also due to differences in labor, GRAIN concluded. Big farms cut labor to maximize profits, and this labor is needed for better production.

“There are multiple factors at play,” Hobbelink told us. “In countries with big population growth, farmers without access to more land are forced to divide their land amongst their children. Expansion of urban areas into farmland, the same for mining, tourism, etc. But perhaps the most important factor is the global expansion of industrial plantation farming encroaching upon areas where small farmers and indigenous peoples live.

“The reason why small farmers still produce the majority of the world’s food is twofold. On one hand–as we show in our report–they are simply more efficient, more productive, than the large industrial plantations. And on the other hand they prioritize their land use towards producing food, while industrial plantations mostly produce commodities that no one can eat, or that need a lot of processing before they end up in our food: soybean, oilpalm, sugarcane, rapeseed, etc.”

“The bottom line is that land is becoming more and more concentrated in the hands of the rich and powerful, not that small farmers are doing well,” GRAIN concluded.

“Today, small farmers feed the world and we need them to continue to do so,” said Hobbelink. “If we don’t reverse the current trend of the corporate takeover of the worlds farmland to produce industrial commodities, they will not be able to do so and we will all lose out.”

Photos: all belong to the work of GRAIN

Language facilitates the global flow of ideas, and elite languages in global communications are those that are both literate and online, according to new research that has mapped information flows across languages. Certain languages have been found to be much more powerful than others, because they are more and better connected within the communications networks of the world, while others are relatively weaker. Some smaller languages are stronger than languages spoken by much larger groups of people however, due to political and other reasons.

“The global influence of a language is determined by its connections to other languages, not by its number of speakers or their economic power, as these connections make possible the global transfer of ideas,” MIT’s Shahar Ronen, first author of the study, told The Speaker.

Ronen explained how some language speakers–those who speak central languages–have a disproportionate amount of power and responsibility because their communications are “tacitly shaping the way in which distant cultures see each other,” while other language groups are handicapping themselves with policies that restrict or disconnect people from global communications networks (GLNs).

“Think about it this way: if the English-speaking world did not care about the 2014 events in Ukraine, the rest of the world would have a very hard time learning about it as well.”

“A government that disconnects its people from the internet–e.g., as China does with its Great Firewall–hamstrings its ability to gain global influence,” said Ronen. “Governments concerned with boosting international soft power should invest in translating more documents and encourage more people to tweet in their national language. Contemporary China and Russia produce very few international thought leaders, and leave little legacy for future generations.”

The study generated maps of connections between communications media–including 30 years worth of book translations in 150 countries, 550 million Tweets in 73 languages, and multiple language editions of Wikipedia pages.

“We mapped three global language networks from three sources: Twitter, Wikipedia and book translations,” Ronen explained. “These sources are by no means representative of the world’s population; rather, they represent the elites that generate and propagate ideas around the world.”

The team found that the more central a given language was to the network, the more famous its speakers were predicted to be–more so than other factors such as population and wealth.

Centrality was based on both strength and number of connections, the team found. The three GLNs identified by the team centered on English as a global hub. That hub is connected to secondary hubs–Spanish, French, German, Portuguese, Chinese and Russian.

“For example, it is easy for an idea conceived by a Spaniard to reach an Englishman through bilingual speakers of English and Spanish,” said Ronen. “An idea conceived by a Vietnamese speaker, however, might only reach a Mapudungun speaker in south-central Chile through a circuitous path that connects bilingual speakers of Vietnamese and English, English and Spanish, and Spanish and Mapudungun.”

Many of the world’s people are to a degree left out of the global conversation–those who do not communicate in an elite language–and these people face profound limitations. This extends to both languages that are not spoken by relatively large amounts of people and languages are spoken by significant populations but that are limited for other reasons, Ronen said.

“The truly disenfranchised, at least as global communication is concerned, are those whose language don’t even show up on our network. That said, speakers of languages such as Chinese or Arabic, both a with low centrality given their number of speakers, are disadvantaged as well, as they are less likely to be exposed to the latest and greatest ideas in their fields and well not be able to communicate theirs globally. Consider a researcher who speaks only Chinese who will not be exposed to work by her peers abroad, or a CEO who speaks only Arabic.”

Ronen highlighted the importance of learning more than one language–particularly top elite languages.

“Learning a new language opens up a new part of the world for the learner and broadens his/her perspective. Achieving reasonable fluency in English is one of the best investments an individual in any country and any occupation can make. If you already speak English, learning another language is still valuable. If you have a specific goal such as doing business in a certain country, learning that country’s language will be highly beneficial.

“If you’re looking for a language that can open new opportunities for you in general, our study can inform you which languages to consider–Spanish or French are great options. From a global point of view, more multilinguals mean more and stronger connections between languages, which in turn facilitate the global flow of ideas.

The report, “Links that speak: The global language network and its association with global fame” was completed by Shahar Ronen, Bruno Gonçalves, Kevin Z. Hu, Alessandro Vespignani, Steven Pinker, and César A. Hidalgo.