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To Really Learn, Quit Studying and Take a Test

By PAM BELLUCK


Taking a test is not just a passive mechanism for assessing how much people know, according to new research. It actually helps people learn, and it works better than a number of other studying techniques.

The research, published online Thursday in the journal Science, found that students who read a passage, then took a test asking them to recall what they had read, retained about 50 percent more of the information a week later than students who used two other methods.

One of those methods — repeatedly studying the material — is familiar to legions of students who cram before exams. The other — having students draw detailed diagrams documenting what they are learning — is prized by many teachers because it forces students to make connections among facts.

These other methods not only are popular, the researchers reported; they also seem to give students the illusion that they know material better than they do.

In the experiments, the students were asked to predict how much they would remember a week after using one of the methods to learn the material. Those who took the test after reading the passage predicted they would remember less than the other students predicted — but the results were just the opposite.

“I think that learning is all about retrieving, all about reconstructing our knowledge,” said the lead author, Jeffrey Karpicke, an assistant professor of psychology at Purdue University. “I think that we’re tapping into something fundamental about how the mind works when we talk about retrieval.”

Several cognitive scientists and education experts said the results were striking.

The students who took the recall tests may “recognize some gaps in their knowledge,” said Marcia Linn, an education professor at the University of California, Berkeley, “and they might revisit the ideas in the back of their mind or the front of their mind.”

When they are later asked what they have learned, she went on, they can more easily “retrieve it and organize the knowledge that they have in a way that makes sense to them.”

The researchers engaged 200 college students in two experiments, assigning them to read several paragraphs about a scientific subject — how the digestive system works, for example, or the different types of vertebrate muscle tissue.

In the first experiment, the students were divided into four groups. One did nothing more than read the text for five minutes. Another studied the passage in four consecutive five-minute sessions.

A third group engaged in “concept mapping,” in which, with the passage in front of them, they arranged information from the passage into a kind of diagram, writing details and ideas in hand-drawn bubbles and linking the bubbles in an organized way.

The final group took a “retrieval practice” test. Without the passage in front of them, they wrote what they remembered in a free-form essay for 10 minutes. Then they reread the passage and took another retrieval practice test.

A week later all four groups were given a short-answer test that assessed their ability to recall facts and draw logical conclusions based on the facts.

The second experiment focused only on concept mapping and retrieval practice testing, with each student doing an exercise using each method. In this initial phase, researchers reported, students who made diagrams while consulting the passage included more detail than students asked to recall what they had just read in an essay.

But when they were evaluated a week later, the students in the testing group did much better than the concept mappers. They even did better when they were evaluated not with a short-answer test but with a test requiring them to draw a concept map from memory.

Why retrieval testing helps is still unknown. Perhaps it is because by remembering information we are organizing it and creating cues and connections that our brains later recognize.

“When you’re retrieving something out of a computer’s memory, you don’t change anything — it’s simple playback,” said Robert Bjork, a psychologist at the University of California, Los Angeles, who was not involved with the study.

But “when we use our memories by retrieving things, we change our access” to that information, Dr. Bjork said. “What we recall becomes more recallable in the future. In a sense you are practicing what you are going to need to do later.”

It may also be that the struggle involved in recalling something helps reinforce it in our brains.

Maybe that is also why students who took retrieval practice tests were less confident about how they would perform a week later.

“The struggle helps you learn, but it makes you feel like you’re not learning,” said Nate Kornell, a psychologist at Williams College. “You feel like: ‘I don’t know it that well. This is hard and I’m having trouble coming up with this information.’ ”

By contrast, he said, when rereading texts and possibly even drawing diagrams, “you say: ‘Oh, this is easier. I read this already.’ ”

The Purdue study supports findings of a recent spate of research showing learning benefits from testing, including benefits when students get questions wrong. But by comparing testing with other methods, the study goes further.

“It really bumps it up a level of importance by contrasting it with concept mapping, which many educators think of as sort of the gold standard,” said Daniel Willingham, a psychology professor at the University of Virginia. Although “it’s not totally obvious that this is shovel-ready — put it in the classroom and it’s good to go — for educators this ought to be a big deal.”

Howard Gardner, an education professor at Harvard who advocates constructivism — the idea that children should discover their own approach to learning, emphasizing reasoning over memorization — said in an e-mail that the results “throw down the gauntlet to those progressive educators, myself included.”

“Educators who embrace seemingly more active approaches, like concept mapping,” he continued, “are challenged to devise outcome measures that can demonstrate the superiority of such constructivist approaches.”

Testing, of course, is a highly charged issue in education, drawing criticism that too much promotes rote learning, swallows valuable time for learning new things and causes excessive student anxiety.

“More testing isn’t necessarily better,” said Dr. Linn, who said her work with California school districts had found that asking students to explain what they did in a science experiment rather than having them simply conduct the hands-on experiment — a version of retrieval practice testing — was beneficial. “Some tests are just not learning opportunities. We need a different kind of testing than we currently have.”

Dr. Kornell said that “even though in the short term it may seem like a waste of time,” retrieval practice appears to “make things stick in a way that may not be used in the classroom.

“It’s going to last for the rest of their schooling, and potentially for the rest of their lives.”

Source: Nytimes/Science Jan 20, 2011

 

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Writing About Testing Worries Boosts Exam Performance in the Classroom

By Gerardo Ramirez and Sian L. Beilock*

Abstract:
Two laboratory and two randomized field experiments tested a psychological intervention designed to improve students’ scores on high-stakes exams and to increase our understanding of why pressure-filled exam situations undermine some students’ performance. We expected that sitting for an important exam leads to worries about the situation and its consequences that undermine test performance. We tested whether having students write down their thoughts about an upcoming test could improve test performance. The intervention, a brief expressive writing assignment that occurred immediately before taking an important test, significantly improved students’ exam scores, especially for students habitually anxious about test taking. Simply writing about one’s worries before a high-stakes exam can boost test scores.

Source: Science 14 January 2011: 211-213

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Attached is the full paper. This article was published in one of the two most prestigious, most-read journals in the sciences.

 

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Want to improve your memory? Walk more .


A Walk to Remember? Study Says Yes

By PAULA SPAN

In healthy adults, the hippocampus — a part of the brain important to the formation of memories — begins to atrophy around 55 or 60. Now psychologists are suggesting that the hippocampus can be modestly expanded, and memory improved, by nothing more than regular walking.

In a study published on Jan. 31 in The Proceedings of the National Academy of Sciences, researchers randomly assigned 120 healthy but sedentary men and women (average age mid-60s) to one of two exercise groups. One group walked around a track three times a week, building up to 40 minutes at a stretch; the other did a variety of less aerobic exercises, including yoga and resistance training with bands.

After a year, brain scans showed that among the walkers, the hippocampus had increased in volume by about 2 percent on average; in the others, it had declined by about 1.4 percent. Since such a decline is normal in older adults, “a 2 percent increase is fairly significant,” said the lead author, Kirk Erickson, a psychologist at the University of Pittsburgh. Both groups also improved on a test of spatial memory, but the walkers improved more.

While it is hard to generalize from this study to other populations, the researchers were delighted to learn that the hippocampus might expand with exercise. “And not that much exercise,” Dr. Erickson pointed out.

People don’t even have to join a gym, he noted. They just need shoes.

Source: Nytimes Feb 7, 2011

 

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Better education, better chance of a longer life

Education reduces blood pressure


Despite exam stress, a long stint in education is good for people's blood pressure, according to researchers in the US.

High blood pressure, or hypertension, is linked to heart attacks, strokes and kidney failure. The study, published in the journal BMC Public Health, shows the link is stronger in women than in men. The British Heart Foundation said the findings supported the link between deprivation and heart disease risk.

Higher levels of education have been linked to lower levels of heart disease. The researchers suggest that blood pressure could be the reason why.

The study looked at 30 years of data from 3,890 people who were being followed as part of the Framingham Offspring Study. People were divided into three groups, low education (12 years or less), middle education (13 to 16 years) and high education (17 years or more). The average systolic blood pressure for the 30 year period was then calculated.

Predisposition

Women with low education had a blood pressure 3.26 mmHg higher than those with a high level of education. In men the difference was 2.26 mmHg. Other factors, such as smoking, taking blood pressure medication and drinking, were taken into consideration and the effect on blood pressure remained, although at a much lower level.

Writing in the journal, the researchers says: "Low educational attainment has been demonstrated to predispose individuals to high strain jobs, characterised by high levels of demand and low levels of control, which have been associated with elevated blood pressure."

Professor Eric Loucks, who conducted the study at Brown University, said: "Women with less education are more likely to be experiencing depression, they are more likely to be single parents, more likely to be living in impoverished areas and more likely to be living below the poverty line."

Natasha Stewart, senior cardiac nurse at the British Heart Foundation, said: "These findings support existing evidence about the link between socio-economic deprivation and heart disease risk. "However, the study only showed up a small blood pressure drop among women and an insignificant decrease among men.

"Action is needed across all parts of society to give children the best possible start in life and reduce health inequalities."

Source: BBC News Feb 28, 2011

 

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It's a long excerpt from a very long article, read the highlighted if you don't have time .

How the new sciences of human nature can help make sense of a life.

BY DAVID BROOKS

After the boom and bust, the mania and the meltdown, the Composure Class rose once again. Its members didn’t make their money through hedge-fund wizardry or by some big financial score. Theirs was a statelier ascent. They got good grades in school, established solid social connections, joined fine companies, medical practices, and law firms. Wealth settled down upon them gradually, like a gentle snow.

You can see a paragon of the Composure Class having an al-fresco lunch at some bistro in Aspen or Jackson Hole. He’s just back from China and stopping by for a corporate board meeting on his way to a five-hundred-mile bike-a-thon to support the fight against lactose intolerance. He is asexually handsome, with a little less body fat than Michelangelo’s David. As he crosses his legs, you observe that they are immeasurably long and slender. He doesn’t really have thighs. Each leg is just one elegant calf on top of another. His voice is so calm and measured that he makes Barack Obama sound like Sam Kinison. He met his wife at the Clinton Global Initiative, where they happened to be wearing the same Doctors Without Borders support bracelets. They are a wonderfully matched pair; the only tension between them involves their workout routines. For some reason, today’s high-status men do a lot of running and biking and so only really work on the muscles in the lower half of their bodies. High-status women, on the other hand, pay ferocious attention to their torsos, biceps, and forearms so they can wear sleeveless dresses all summer and crush rocks with their bare hands.

A few times a year, members of this class head to a mountain resort, carrying only a Council on Foreign Relations tote bag (when you have your own plane, you don’t need luggage that actually closes). Once there, they play with hundred-and-sixty-pound dogs, for it has become fashionable to have canines a third as tall as the height of your ceilings. They will reflect on the genetic miracle they have achieved. (Their grandmothers looked like Gertrude Stein, but their granddaughters look like Uma Thurman.) In the evenings, they will traipse through resort-community pedestrian malls licking interesting gelatos, while passersby burst into spontaneous applause.

Occasionally, you meet a young, rising member of this class at the gelato store, as he hovers indecisively over the cloudberry and ginger-pomegranate selections, and you notice that his superhuman equilibrium is marred by an anxiety. Many members of this class, like many Americans generally, have a vague sense that their lives have been distorted by a giant cultural bias. They live in a society that prizes the development of career skills but is inarticulate when it comes to the things that matter most. The young achievers are tutored in every soccer technique and calculus problem, but when it comes to their most important decisions—whom to marry and whom to befriend, what to love and what to despise—they are on their own. Nor, for all their striving, do they understand the qualities that lead to the highest achievement. Intelligence, academic performance, and prestigious schools don’t correlate well with fulfillment, or even with outstanding accomplishment. The traits that do make a difference are poorly understood, and can’t be taught in a classroom, no matter what the tuition: the ability to understand and inspire people; to read situations and discern the underlying patterns; to build trusting relationships; to recognize and correct one’s shortcomings; to imagine alternate futures. In short, these achievers have a sense that they are shallower than they need to be.


elp comes from the strangest places. We are living in the middle of a revolution in consciousness. Over the past few decades, geneticists, neuroscientists, psychologists, sociologists, economists, and others have made great strides in understanding the inner working of the human mind. Far from being dryly materialistic, their work illuminates the rich underwater world where character is formed and wisdom grows. They are giving us a better grasp of emotions, intuitions, biases, longings, predispositions, character traits, and social bonding, precisely those things about which our culture has least to say. Brain science helps fill the hole left by the atrophy of theology and philosophy.

A core finding of this work is that we are not primarily the products of our conscious thinking. The conscious mind gives us one way of making sense of our environment. But the unconscious mind gives us other, more supple ways. The cognitive revolution of the past thirty years provides a different perspective on our lives, one that emphasizes the relative importance of emotion over pure reason, social connections over individual choice, moral intuition over abstract logic, perceptiveness over I.Q. It allows us to tell a different sort of success story, an inner story to go along with the conventional surface one.

To give a sense of how this inner story goes, let’s consider a young member of the Composure Class, though of course the lessons apply to members of all classes. I’ll call him Harold. His inner-mind training began before birth. Even when he was in the womb, Harold was listening for his mother’s voice, and being molded by it. French babies cry differently from babies who’ve heard German in the womb, because they’ve absorbed French intonations before birth. Fetuses who have been read “The Cat in the Hat” while in the womb suck rhythmically when they hear it again after birth, because they recognize the rhythm of the poetry.

As a newborn, Harold, like all babies, was connecting with his mother. He gazed at her. He mimicked. His brain was wired by her love (the more a rat pup is licked and groomed by its mother, the more synaptic connections it has). Harold’s mother, in return, read his moods. A conversation developed between them, based on touch, gaze, smell, rhythm, and imitation. When Harold was about eleven months old, his mother realized that she knew him better than she’d ever known anybody, even though they’d never exchanged a word.

Harold soon developed models in his head of how to communicate with people and how to use others as tools for his own learning. Thanks to his mom’s attunement, he became confident that if he sent a signal it would be received. Later in life, his sense of security enabled him to go out and explore the world. Researchers at the University of Minnesota can look at attachment patterns of children at forty-two months, and predict with seventy-seven-per-cent accuracy who will graduate from high school. People who were securely attached as infants tend to have more friends at school and at summer camp. They tend to be more truthful through life, feeling less need to puff themselves up in others’ eyes. According to work by Pascal Vrticka, of the University of Geneva, people with what scientists call “avoidant attachment patterns” show less activation in the reward areas of the brain during social interaction. Men who had unhappy childhoods are three times as likely to be solitary at age seventy. Early experiences don’t determine a life, but they set pathways, which can be changed or reinforced by later experiences.

For several months when he was four, Harold insisted that he was a tiger who had been born on the sun. His parents tried to get him to concede that he was a little boy born in a hospital, but he would become grave and refuse. This formulation, “I’m a tiger,” may seem like an easy thing, but no computer could blend the complicated concept “I” with the complicated concept “tiger” into a single entity. As Harold grew, he was able to use his imagination to blend disparate ideas, in the same sort of way that Picasso, at the height of his creative powers, could combine the concept “Western portraiture” with the concept “African masks.”

Throughout his life, Harold had a superior ability to feel what others were feeling. He didn’t dazzle his teachers with academic brilliance, but, even in kindergarten, he could tell you who in his class was friends with whom; he was aware of social networks. Scientists used to think that we understand each other by observing each other and building hypotheses from the accumulated data. Now it seems more likely that we are, essentially, method actors who understand others by simulating the responses we see in them. When Harold was in high school, he could walk around the cafeteria and fall in with the unique social patterns that prevailed in each clique. He could tell which clique tolerated drug use or country-music listening and which didn’t. He could tell how many guys a girl could hook up with and not be stigmatized. In some groups, the number was three; in others seven. Most people assume that the groups they don’t belong to are more homogeneous than the groups they do belong to. Harold could see groups from the inside. When he sat down with, say, the Model U.N. kids, he could guess which one of them wanted to migrate from the Geeks and join the Honors/Athletes. He could sense who was the leader of any group, who was the jester, who played the role of peacemaker, daredevil, organizer, or self-effacing audience member.

One of Harold’s key skills in school was his ability to bond with teachers. We’ve spent a generation trying to reorganize schools to make them better, but the truth is that people learn from the people they love. In eleventh grade, Harold developed a crush on his history teacher, Ms. Taylor. What mattered most was not the substance of the course so much as the way she thought, the style of learning she fostered. For instance, Ms. Taylor constantly told the class how little she knew. Human beings are overconfidence machines. Paul J. H. Schoemaker and J. Edward Russo gave questionnaires to more than two thousand executives in order to measure how much they knew about their industries. Managers in the advertising industry gave answers that they were ninety-per-cent confident were correct. In fact, their answers were wrong sixty-one per cent of the time. People in the computer industry gave answers they thought had a ninety-five per cent chance of being right; in fact, eighty per cent of them were wrong. Ninety-nine per cent of the respondents overestimated their success.

Ms. Taylor was always reminding the class of how limited her grasp of any situation was. “Sorry, I get distracted easily,” she’d say, or, “Sorry, sometimes I jump to conclusions too quickly.” In this way, she communicated the distinction between mental strength (the processing power of the brain) and mental character (the mental virtues that lead to practical wisdom). She stressed the importance of collecting conflicting information before making up one’s mind, of calibrating one’s certainty level to the strength of the evidence, of enduring uncertainty for long stretches as an answer became clear, of correcting for one’s biases. As Keith E. Stanovich, a psychologist at the University of Toronto, writes in his book “What Intelligence Tests Miss” (2009), these “thinking dispositions” correlate weakly or not at all with I.Q. But, because Ms. Taylor put such emphasis on these virtues and because Harold admired her so much, he absorbed and copied her way of being.

By the time Harold was in his mid-twenties, he was well on his way toward a happy and fulfilling life, and the building blocks of his happiness had little to do with the lines on his résumé. There’s a debate in our culture about what really makes us happy, which is summarized by, on the one hand, the book “On the Road” and, on the other, the movie “It’s a Wonderful Life.” The former celebrates the life of freedom and adventure. The latter celebrates roots and connections. Research over the past thirty years makes it clear that what the inner mind really wants is connection. “It’s a Wonderful Life” was right. Joining a group that meets just once a month produces the same increase in happiness as doubling your income. According to research by Daniel Kahneman, Alan B. Krueger, and others, the daily activities most closely associated with happiness are social—having sex, socializing after work, and having dinner with friends. Many of the professions that correlate most closely with happiness are also social—a corporate manager, a hairdresser.

[...]

“And though history has made us self-conscious in order to enhance our survival prospects, we still have deep impulses to erase the skull lines in our head and become immersed directly in the river. I’ve come to think that flourishing consists of putting yourself in situations in which you lose self-consciousness and become fused with other people, experiences, or tasks. It happens sometimes when you are lost in a hard challenge, or when an artist or a craftsman becomes one with the brush or the tool. It happens sometimes while you’re playing sports, or listening to music or lost in a story, or to some people when they feel enveloped by God’s love. And it happens most when we connect with other people. I’ve come to think that happiness isn’t really produced by conscious accomplishments. Happiness is a measure of how thickly the unconscious parts of our minds are intertwined with other people and with activities. Happiness is determined by how much information and affection flows through us covertly every day and year.”

As the scientist went on to talk about the rush he got from riding his motorcycle in the mountains, Harold was gripped by the thought that, during his lifetime, the competition to succeed—to get into the right schools and land the right jobs—had grown stiffer. Society had responded by becoming more and more focussed. Yet somehow the things that didn’t lead to happiness and flourishing had been emphasized at the expense of the things that did. The gifts he was most grateful for had been passed along to him by teachers and parents inadvertently, whereas his official education was mostly forgotten or useless.

Moreover, Harold had the sense that he had been trained to react in all sorts of stupid ways. He had been trained, as a guy, to be self-contained and smart and rational, and to avoid sentimentality. Yet maybe sentiments were at the core of everything. He’d been taught to think vertically, moving ever upward, whereas maybe the most productive connections were horizontal, with peers. He’d been taught that intelligence was the most important trait. There weren’t even words for the traits that matter most—having a sense of the contours of reality, being aware of how things flow, having the ability to read situations the way a master seaman reads the rhythm of the ocean. Harold concluded that it might be time for a revolution in his own consciousness—time to take the proto-conversations that had been shoved to the periphery of life and put them back in the center. Maybe it was time to use this science to cultivate an entirely different viewpoint.

He’d spent years struggling to dazzle his Mandarin tutors while excelling in obscure sports, trying (not too successfully) to impress admissions officers with S.A.T. prowess and water-purification work in Zambia, sweating to wow his bosses with not overlong PowerPoints.

But maybe the real action was in this deeper layer. After all, the conscious mind chooses what we buy, but the unconscious mind chooses what we like.


Source: The New Yorker Jan 17, 2011

 

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Hôm qua tìm được cái này nên phải share ngay. Bài này trên tạp chì khoa học "Science"—one of the world's most cited scientific journals, having an impact factor second only to Nature's (theo Wiki).

125 biggest unsolved problems in science​

(Nhân kỷ niệm 125 năm của Science)

***​

Bài này hơi cũ, đăng năm 2005, nhưng chắc chắn còn rất nhiều vấn đề chưa được giải quyết trong gần 6 năm vừa qua. Giải quyết được một trong những vấn đề này có thể nói gần như chắc chắn sẽ đem lại một giải Nobel . Về cá nhân, vấn để HA cảm thấy hứng thú là Protein Folding và sự liên hệ của nó với một số neurodegenerative diseases ví dụ như prion diseases, Alzheimer's hay Parkinson's disease.

Các bạn có thể tìm đọc thêm miễn phí ở đây (không cần subscription). Vì lý do gì đó bản pdf của article trong tạp chí không gửi kèm trong bài này được :-/ (?), mà ai hứng thú HA có thể gửi đến e-mail hoặc upload lên đâu đó!

25 vấn đề tiêu biểu trong số đó:

1. What Is the Universe Made Of?
   [*]What is the Biological Basis of Consciousness?
   [*]Why Do Humans Have So Few Genes?
   [*]To What Extent Are Genetic Variation and Personal Health Linked?
   [*]Can the Laws of Physics Be Unified?
   [*]How Much Can Human Life Span Be Extended?
   [*]What Controls Organ Regeneration?
   [*]How Can a Skin Cell Become a Nerve Cell?
   [*]How Does a Single Somatic Cell Become a Whole Plant?
   [*]How Does Earth's Interior Work?
   [*]Are We Alone in the Universe?
   [*]How and Where Did Life on Earth Arise?
   [*]What Determines Species Diversity?
   [*]What Genetic Changes Made Us Uniquely Human?
   [*]How Are Memories Stored and Retrieved?
   [*]How Did Cooperative Behavior Evolve?
   [*]How Will Big Pictures Emerge from a Sea of Biological Data?
   [*]How Far Can We Push Chemical Self-Assembly?
   [*]What Are the Limits of Conventional Computing?
   [*]Can We Selectively Shut Off Immune Responses?
   [*]Do Deeper Principles Underlie Quantum Uncertainty and Nonlocality?
   [*]Is an Effective HIV Vaccine Feasible?
   [*]How Hot Will the Greenhouse World Be?
   [*]What Can Replace Cheap Oil -- and When?
   [*]Will Malthus Continue to Be Wrong?
   

Danh sách và tóm tắt của 100 vấn đề còn lại được trích dưới đây:

Bạn nào có hứng thú đặc biệt trong Toán học có thể xem những vấn đề được liệt kê ở cuối cùng (sau đoạn in nghiêng màu xanh).


Source: Science Magazine

So Much More to Know …​

***
​

From the nature of the cosmos to the nature of societies, the following 100 questions span the sciences. Some are pieces of questions discussed above; others are big questions in their own right. Some will drive scientific inquiry for the next century; others may soon be answered. Many will undoubtedly spawn new questions.

Is ours the only universe?

A number of quantum theorists and cosmologists are trying to figure out whether our universe is part of a bigger “multiverse.” But others suspect that this hard-to-test idea may be a question for philosophers.​

What drove cosmic inflation?

In the first moments after the big bang, the universe blew up at an incredible rate. But what did the blowing? Measurements of the cosmic microwave background and other astrophysical observations are narrowing the possibilities.​

When and how did the first stars and galaxies form?

The broad brush strokes are visible, but the fine details aren't. Data from satellites and ground-based telescopes may soon help pinpoint, among other particulars, when the first generation of stars burned off the hydrogen “fog” that filled the universe.​

Where do ultrahigh-energy cosmic rays come from?

Above a certain energy, cosmic rays don't travel very far before being destroyed. So why are cosmic-ray hunters spotting such rays with no obvious source within our galaxy?​

What powers quasars?

The mightiest energy fountains in the universe probably get their power from matter plunging into whirling supermassive black holes. But the details of what drives their jets remain anybody's guess.​

What is the nature of black holes?

Relativistic mass crammed into a quantum-sized object? It's a recipe for disaster—and scientists are still trying to figure out the ingredients.​

Why is there more matter than antimatter?

To a particle physicist, matter and antimatter are almost the same. Some subtle difference must explain why matter is common and antimatter rare.​

Does the proton decay?

In a theory of everything, quarks (which make up protons) should somehow be convertible to leptons (such as electrons)—so catching a proton decaying into something else might reveal new laws of particle physics.​

What is the nature of gravity?

It clashes with quantum theory. It doesn't fit in the Standard Model. Nobody has spotted the particle that is responsible for it. Newton's apple contained a whole can of worms.​

Why is time different from other dimensions?

It took millennia for scientists to realize that time is a dimension, like the three spatial dimensions, and that time and space are inextricably linked. The equations make sense, but they don't satisfy those who ask why we perceive a “now” or why time seems to flow the way it does.​

Are there smaller building blocks than quarks?

Atoms were “uncuttable.” Then scientists discovered protons, neutrons, and other subatomic particles—which were, in turn, shown to be made up of quarks and gluons. Is there something more fundamental still?​

Are neutrinos their own antiparticles?

Nobody knows this basic fact about neutrinos, although a number of underground experiments are under way. Answering this question may be a crucial step to understanding the origin of matter in the universe.​

Is there a unified theory explaining all correlated electron systems?

High-temperature superconductors and materials with giant and colossal magnetoresistance are all governed by the collective rather than individual behavior of electrons. There is currently no common framework for understanding them.​

What is the most powerful laser researchers can build?

Theorists say an intense enough laser field would rip photons into electron-positron pairs, dousing the beam. But no one knows whether it's possible to reach that point.​

Can researchers make a perfect optical lens?

They've done it with microwaves but never with visible light.​

Is it possible to create magnetic semiconductors that work at room temperature?

Such devices have been demonstrated at low temperatures but not yet in a range warm enough for spintronics applications.​

What is the pairing mechanism behind high-temperature superconductivity?

Electrons in superconductors surf together in pairs. After 2 decades of intense study, no one knows what holds them together in the complex, high-temperature materials.​

Can we develop a general theory of the dynamics of turbulent flows and the motion of granular materials?

So far, such “nonequilibrium systems” defy the tool kit of statistical mechanics, and the failure leaves a gaping hole in physics.​

Are there stable high-atomic-number elements?

A superheavy element with 184 neutrons and 114 protons should be relatively stable, if physicists can create it.​

Is superfluidity possible in a solid? If so, how?

Despite hints in solid helium, nobody is sure whether a crystalline material can flow without resistance. If new types of experiments show that such outlandish behavior is possible, theorists would have to explain how.​

What is the structure of water?

Researchers continue to tussle over how many bonds each H2O molecule makes with its nearest neighbors.​

What is the nature of the glassy state?

Molecules in a glass are arranged much like those in liquids but are more tightly packed. Where and why does liquid end and glass begin?​

Are there limits to rational chemical synthesis?

The larger synthetic molecules get, the harder it is to control their shapes and make enough copies of them to be useful. Chemists will need new tools to keep their creations growing.​

What is the ultimate efficiency of photovoltaic cells?

Conventional solar cells top out at converting 32% of the energy in sunlight to electricity. Can researchers break through the barrier?​

Will fusion always be the energy source of the future?

It's been 35 years away for about 50 years, and unless the international community gets its act together, it'll be 35 years away for many decades to come.​

What drives the solar magnetic cycle?

Scientists believe differing rates of rotation from place to place on the sun underlie its 22-year sunspot cycle. They just can't make it work in their simulations. Either a detail is askew, or it's back to the drawing board.
​

How do planets form?

How bits of dust and ice and gobs of gas came together to form the planets without the sun devouring them all is still unclear. Planetary systems around other stars should provide clues.​

What causes ice ages?

Something about the way the planet tilts, wobbles, and careens around the sun presumably brings on ice ages every 100,000 years or so, but reams of climate records haven't explained exactly how.​

What causes reversals in Earth's magnetic field?

Computer models and laboratory experiments are generating new data on how Earth's magnetic poles might flip-flop. The trick will be matching simulations to enough aspects of the magnetic field beyond the inaccessible core to build a convincing case.​

Are there earthquake precursors that can lead to useful predictions?

Prospects for finding signs of an imminent quake have been waning since the 1970s. Understanding faults will progress, but routine prediction would require an as-yet-unimagined breakthrough.​

Is there—or was there—life elsewhere in the solar system?

The search for life—past or present—on other planetary bodies now drives NASA's planetary exploration program, which focuses on Mars, where water abounded when life might have first arisen.​

What is the origin of homochirality in nature?

Most biomolecules can be synthesized in mirror-image shapes. Yet in organisms, amino acids are always left-handed, and sugars are always right-handed. The origins of this preference remain a mystery.​

Can we predict how proteins will fold?

Out of a near infinitude of possible ways to fold, a protein picks one in just tens of microseconds. The same task takes 30 years of computer time.​

How many proteins are there in humans?

It has been hard enough counting genes. Proteins can be spliced in different ways and decorated with numerous functional groups, all of which makes counting their numbers impossible for now.​

How do proteins find their partners?

Protein-protein interactions are at the heart of life. To understand how partners come together in precise orientations in seconds, researchers need to know more about the cell's biochemistry and structural organization.​

How many forms of cell death are there?

In the 1970s, apoptosis was finally recognized as distinct from necrosis. Some biologists now argue that the cell death story is even more complicated. Identifying new ways cells die could lead to better treatments for cancer and degenerative diseases.​

What keeps intracellular traffic running smoothly?

Membranes inside cells transport key nutrients around, and through, various cell compartments without sticking to each other or losing their way. Insights into how membranes stay on track could help conquer diseases, such as cystic fibrosis.​

What enables cellular components to copy themselves independent of DNA?

Centrosomes, which help pull apart paired chromosomes, and other organelles replicate on their own time, without DNA's guidance. This independence still defies explanation.​

What roles do different forms of RNA play in genome function?

RNA is turning out to play a dizzying assortment of roles, from potentially passing genetic information to offspring to muting gene expression. Scientists are scrambling to decipher this versatile molecule.​

What role do telomeres and centromeres play in genome function?

These chromosome features will remain mysteries until new technologies can sequence them.​

Why are some genomes really big and others quite compact?

The puffer fish genome is 400 million bases; one lungfish's is 133 billion bases long. Repetitive and duplicated DNA don't explain why this and other size differences exist.​

What is all that “junk” doing in our genomes?

DNA between genes is proving important for genome function and the evolution of new species. Comparative sequencing, microarray studies, and lab work are helping genomicists find a multitude of genetic gems amid the junk.​

How much will new technologies lower the cost of sequencing?

New tools and conceptual breakthroughs are driving the cost of DNA sequencing down by orders of magnitude. The reductions are enabling research from personalized medicine to evolutionary biology to thrive.​

How do organs and whole organisms know when to stop growing?

A person's right and left legs almost always end up the same length, and the hearts of mice and elephants each fit the proper rib cage. How genes set limits on cell size and number continues to mystify.​

How can genome changes other than mutations be inherited?

Researchers are finding ever more examples of this process, called epigenetics, but they can't explain what causes and preserves the changes.​

How is asymmetry determined in the embryo?

Whirling cilia help an embryo tell its left from its right, but scientists are still looking for the first factors that give a relatively uniform ball of cells a head, tail, front, and back.​

How do limbs, fins, and faces develop and evolve?

The genes that determine the length of a nose or the breadth of a wing are subject to natural and sexual selection. Understanding how selection works could lead to new ideas about the mechanics of evolution with respect to development.​

What triggers puberty?

Nutrition—including that received in utero—seems to help set this mysterious biological clock, but no one knows exactly what forces childhood to end.​

Are stem cells at the heart of all cancers?

The most aggressive cancer cells look a lot like stem cells. If cancers are caused by stem cells gone awry, studies of a cell's “stemness” may lead to tools that could catch tumors sooner and destroy them more effectively.​

Is cancer susceptible to immune control?

Although our immune responses can suppress tumor growth, tumor cells can combat those responses with counter-measures. This defense can stymie researchers hoping to develop immune therapies against cancer.​

Can cancers be controlled rather than cured?

Drugs that cut off a tumor's fuel supplies—say, by stopping blood-vessel growth—can safely check or even reverse tumor growth. But how long the drugs remain effective is still unknown.​

Is inflammation a major factor in all chronic diseases?

It's a driver of arthritis, but cancer and heart disease? More and more, the answer seems to be yes, and the question remains why and how.​

How do prion diseases work?

Even if one accepts that prions are just misfolded proteins, many mysteries remain. How can they go from the gut to the brain, and how do they kill cells once there, for example.​

How much do vertebrates depend on the innate immune system to fight infection?

This system predates the vertebrate adaptive immune response. Its relative importance is unclear, but immunologists are working to find out.​

Does immunologic memory require chronic exposure to antigens?

Yes, say a few prominent thinkers, but experiments with mice now challenge the theory. Putting the debate to rest would require proving that something is not there, so the question likely will not go away.​

Why doesn't a pregnant woman reject her fetus?

Recent evidence suggests that the mother's immune system doesn't “realize” that the fetus is foreign even though it gets half its genes from the father. Yet just as Nobelist Peter Medawar said when he first raised this question in 1952, “the verdict has yet to be returned.”​

What synchronizes an organism's circadian clocks?

Circadian clock genes have popped up in all types of creatures and in many parts of the body. Now the challenge is figuring out how all the gears fit together and what keeps the clocks set to the same time.​

How do migrating organisms find their way?

Birds, butterflies, and whales make annual journeys of thousands of kilometers. They rely on cues such as stars and magnetic fields, but the details remain unclear.​

Why do we sleep?

A sound slumber may refresh muscles and organs or keep animals safe from dangers lurking in the dark. But the real secret of sleep probably resides in the brain, which is anything but still while we're snoring away.​

Why do we dream?

Freud thought dreaming provides an outlet for our unconscious desires. Now, neuroscientists suspect that brain activity during REM sleep—when dreams occur—is crucial for learning. Is the experience of dreaming just a side effect?​

Why are there critical periods for language learning?

Monitoring brain activity in young children—including infants—may shed light on why children pick up languages with ease while adults often struggle to learn train station basics in a foreign tongue.​

Do pheromones influence human behavior?

Many animals use airborne chemicals to communicate, particularly when mating. Controversial studies have hinted that humans too use pheromones. Identifying them will be key to assessing their sway on our social lives.​

How do general anesthetics work?

Scientists are chipping away at the drugs' effects on individual neurons, but understanding how they render us unconscious will be a tougher nut to crack.​

What causes schizophrenia?

Researchers are trying to track down genes involved in this disorder. Clues may also come from research on traits schizophrenics share with normal people.​

What causes autism?

Many genes probably contribute to this baffling disorder, as well as unknown environmental factors. A biomarker for early diagnosis would help improve existing therapy, but a cure is a distant hope.​

To what extent can we stave off Alzheimer's?

A 5- to 10-year delay in this late-onset disease would improve old age for millions. Researchers are determining whether treatments with hormones or antioxidants, or mental and physical exercise, will help.​

What is the biological basis of addiction?

Addiction involves the disruption of the brain's reward circuitry. But personality traits such as impulsivity and sensation-seeking also play a part in this complex behavior.​

Is morality hardwired into the brain?

That question has long puzzled philosophers; now some neuroscientists think brain imaging will reveal circuits involved in reasoning.​

What are the limits of learning by machines?

Computers can already beat the world's best chess players, and they have a wealth of information on the Web to draw on. But abstract reasoning is still beyond any machine.​

How much of personality is genetic?

Aspects of personality are influenced by genes; environment modifies the genetic effects. The relative contributions remain under debate.​

What is the biological root of sexual orientation?

Much of the “environmental” contribution to homosexuality may occur before birth in the form of prenatal hormones, so answering this question will require more than just the hunt for “gay genes.”​

Will there ever be a tree of life that systematists can agree on?

Despite better morphological, molecular, and statistical methods, researchers' trees don't agree. Expect greater, but not complete, consensus.​

How many species are there on Earth?

Count all the stars in the sky? Impossible. Count all the species on Earth? Ditto. But the biodiversity crisis demands that we try.​

What is a species?

A “simple” concept that's been muddied by evolutionary data; a clear definition may be a long time in coming.​

Why does lateral transfer occur in so many species and how?

Once considered rare, gene swapping, particularly among microbes, is proving quite common. But why and how genes are so mobile—and the effect on fitness—remains to be determined.​

Who was LUCA (the last universal common ancestor)?

Ideas about the origin of the 1.5-billion-year-old “mother” of all complex organisms abound. The continued discovery of primitive microbes, along with comparative genomics, should help resolve life's deep past.​

How did flowers evolve?

Darwin called this question an “abominable mystery.” Flowers arose in the cycads and conifers, but the details of their evolution remain obscure.​

How do plants make cell walls?

Cellulose and pectin walls surround cells, keeping water in and supporting tall trees. The biochemistry holds the secrets to turning its biomass into fuel.​

How is plant growth controlled?

Redwoods grow to be hundreds of meters tall, Arctic willows barely 10 centimeters. Understanding the difference could lead to higher-yielding crops.​

Why aren't all plants immune to all diseases?

Plants can mount a general immune response, but they also maintain molecular snipers that take out specific pathogens. Plant pathologists are asking why different species, even closely related ones, have different sets of defenders. The answer could result in hardier crops.​

What is the basis of variation in stress tolerance in plants?

We need crops that better withstand drought, cold, and other stresses. But there are so many genes involved, in complex interactions, that no one has yet figured out which ones work how.​

What caused mass extinctions?

A huge impact did in the dinosaurs, but the search for other catastrophic triggers of extinction has had no luck so far. If more subtle or stealthy culprits are to blame, they will take considerably longer to find.​

Can we prevent extinction?

Finding cost-effective and politically feasible ways to save many endangered species requires creative thinking.​

Why were some dinosaurs so large?

Dinosaurs reached almost unimaginable sizes, some in less than 20 years. But how did the long-necked sauropods, for instance, eat enough to pack on up to 100 tons without denuding their world?​

How will ecosystems respond to global warming?

To anticipate the effects of the intensifying greenhouse, climate modelers will have to focus on regional changes and ecologists on the right combination of environmental changes.​

How many kinds of humans coexisted in the recent past, and how did they relate?

The new dwarf human species fossil from Indonesia suggests that at least four kinds of humans thrived in the past 100,000 years. Better dates and additional material will help confirm or revise this picture.​

What gave rise to modern human behavior?

Did Homo sapiens acquire abstract thought, language, and art gradually or in a cultural “big bang,” which in Europe occurred about 40,000 years ago? Data from Africa, where our species arose, may hold the key to the answer.​

What are the roots of human culture?

No animal comes close to having humans' ability to build on previous discoveries and pass the improvements on. What determines those differences could help us understand how human culture evolved.​

What are the evolutionary roots of language and music?

Neuroscientists exploring how we speak and make music are just beginning to find clues as to how these prized abilities arose.​

What are human races, and how did they develop?

Anthropologists have long argued that race lacks biological reality. But our genetic makeup does vary with geographic origin and as such raises political and ethical as well as scientific questions.​

Why do some countries grow and others stagnate?

From Norway to Nigeria, living standards across countries vary enormously, and they're not becoming more equal.​

What impact do large government deficits have on a country's interest rates and economic growth rate?

The United States could provide a test case.​

Are political and economic freedom closely tied?

China may provide one answer.​

Why has poverty increased and life expectancy declined in sub-Saharan Africa?

Almost all efforts to reduce poverty in sub-Saharan Africa have failed. Figuring out what will work is crucial to alleviating massive human suffering.​

The following six mathematics questions are drawn from a list of seven outstanding problems selected by the Clay Mathematics Institute. (The seventh problem is discussed on p.96.) For more details, go to www.claymath.org/millennium.

Is there a simple test for determining whether an elliptic curve has an infinite number of rational solutions?

Equations of the form y2 = x3 + ax + b are powerful mathematical tools. The Birch and Swinnerton-Dyer conjecture tells how to determine how many solutions they have in the realm of rational numbers—information that could solve a host of problems, if the conjecture is true.​

Can a Hodge cycle be written as a sum of algebraic cycles?

Two useful mathematical structures arose independently in geometry and in abstract algebra. The Hodge conjecture posits a surprising link between them, but the bridge remains to be built.​

Will mathematicians unleash the power of the Navier-Stokes equations?

First written down in the 1840s, the equations hold the keys to understanding both smooth and turbulent flow. To harness them, though, theorists must find out exactly when they work and under what conditions they break down.​

Does Poincaré's test identify spheres in four-dimensional space?

You can tie a string around a doughnut, but it will slide right off a sphere. The mathematical principle behind that observation can reliably spot every spherelike object in 3D space. Henri Poincaré conjectured that it should also work in the next dimension up, but no one has proved it yet.​

Do mathematically interesting zero-value solutions of the Riemann zeta function all have the form a + bi?

Don't sweat the details. Since the mid-19th century, the “Riemann hypothesis” has been the monster catfish in mathematicians' pond. If true, it will give them a wealth of information about the distribution of prime numbers and other long-standing mysteries.​

Does the Standard Model of particle physics rest on solid mathematical foundations?

For almost 50 years, the model has rested on “quantum Yang-Mills theory,” which links the behavior of particles to structures found in geometry. The theory is breathtakingly elegant and useful—but no one has proved that it's sound.​

 

[Lê Hải Anh (haianhle)]

Think carefully before going for PhD:

Fix the PhD
​

The world has many problems and it will take a lot of bright, educated people to solve them. So, on the face of it, it seems like a good thing that more and more people are earning PhDs in science, technology and engineering. Most countries, convinced that higher education and scientific research are key to economic growth and prosperity, are expanding doctoral education in science. The thought, as one researcher who has studied doctoral-education trends puts it, is that you can “grow PhDs like mushrooms”.

The consequence of that mushrooming depends on where it is taking place, and in which discipline, as our overview of PhD systems around the world shows (see page 276). Clearly, such expansion results in an extraordinary amount of good research (see page 283). And in the rapidly growing tiger economies, for example, most of those with PhDs quickly find good jobs.

But there are reasons for caution. Unlimited growth could dilute the quality of PhDs by pulling less-able individuals into the system. And casual chats with biomedical researchers in the United States or Japan suggest a gloomy picture. Exceptionally bright science PhD holders from elite academic institutions are slogging through five or ten years of poorly paid postdoctoral studies, slowly becoming disillusioned by the ruthless and often fruitless fight for a permanent academic position. That is because increased government research funding from the US National Institutes of Health and Japan's science and education ministry has driven expansion of doctoral and postdoctoral education — without giving enough thought to how the labour market will accommodate those who emerge. The system is driven by the supply of research funding, not the demand of the job market.

“Widening concerns about dismal job prospects are dissuading the brightest candidates from the PhD route.”
The problem is widely discussed, yet many PhD programmes remain firmly in the traditional mould — offering an apprenticeship for academic research, even as numbers of academic positions stagnate or decline. Yes, there are many worthwhile careers outside academia for science PhD holders (Nature would be down to a skeleton staff without them). And most people with science PhDs eventually find satisfying jobs. But they probably feel that spending years performing minipreps was not the most appropriate way to become a banker or a teacher. Widening concerns about dismal job prospects are dissuading some of the brightest candidates from taking the PhD route.

Something needs to change — but what? Ideally, the system would produce high-quality PhD holders well matched to the attractive careers on offer. Yet many academics are reluctant to rock the boat as long as they are rewarded with grants (which pay for cheap PhD students) and publications (produced by their cheap PhD students). So are universities, which often receive government subsidies to fill their PhD spots.

One way in which governments can bring about change is to better match educational supply with occupational demand. They should get smart, independent labour economists to comb through wage and employment data that reveal which types of science-related job are in short supply, and talk to stakeholders on the ground to confirm the findings. Governments should then open the doors to more PhDs only where they are most needed. Such analyses are already under way, and should be encouraged.

A second route is to reform the PhD itself (see page 261), and reset the expectations of those in the system. Imagine bright young things entering a new kind of science PhD, in which both they and their supervisors embrace from the start the idea that graduates will go on to an array of demanding careers — government, business, non-profit and education — and work towards that goal (see page 381). The students meet supervisors from a range of disciplines; they acquire management, communication, leadership and other transferable skills alongside traditional academic development of critical thinking and analysis; and they spend six months to a year abroad.

Some such efforts have already begun: for example, US institutions vie to win prestigious grants from the Integrative Graduate Education and Research Traineeship (IGERT) programme run by the National Science Foundation, which promotes highly interdisciplinary PhDs (see page 280)

The IGERT scheme shows how appropriate reward structures can drive change. Governments and funding agencies should require educational institutions to release figures showing how many of their PhD students complete the course, and how many go on to find employment and where, and should award some proportion of funding accordingly. This would also help prospective students to select a good course, and force worse-performing programmes to shape up or close.

Until any of this becomes commonplace, it is up to prospective graduate students to enter a science PhD with their eyes open to the opportunities — or lack of them — at the end. Not all mushrooms grow best in the dark.

Source: Nature 472, 259–260 (21 April 2011)

 

[Lê Hải Anh (haianhle)]

What is a PhD really worth?

byPeter Fiske

An advanced degree doesn't always bring the prospects it once did, says Peter Fiske. But scientists can learn from the travails of those with professional qualifications.

In the past few months there has been a string of articles1, 2 in the Western press about the poor career prospects of graduates from professional schools, especially law school. Thanks to a dismal job market, applications to such institutions surged during the recession. Now, a few years later, those applicants are graduating into a career market that is only slightly better — and many have become saddled with debt.

Professional schools are now encountering the graduate-overproduction issues with which PhD programmes have been wrestling for decades. Entry to law school or medical school once provided a near-certainty of gainful (and often highly lucrative) employment after graduation, but the alumni of these programmes are now struggling to find their first jobs. Many are blaming their graduate schools for promulgating misleading information about their job prospects.

Sound familiar? In the late 1980s, the US National Science Foundation and other groups spread the notion that a wave of retirement was about to sweep through academia, and that the academic job prospects for emerging PhDs had never been brighter. In fact, the economic assumptions that formed the basis of this prediction were erroneous3, and no such wave of retirement took place. In the early 1990s, PhD holders (including myself) spilled into the job market with essentially no guidance on how to find employment outside the ivory tower. The ensuing backlash from young scientists forced the academic establishment to acknowledge that it was producing many more scientific PhDs than it could accommodate in tenured positions. More importantly, the establishment had to recognize that PhD scientists could find satisfying and valuable careers outside academia. Although many graduate-student scientists still have their hopes fixed on academic positions, they are now also exploring a range of career options in industry, government and the non-profit sector.

Lessons for life
The predicament of the current crop of law- and medical-school graduates might give PhD students an opportunity for Schadenfreude. But I think that young scientists — and the academic institutions from which they come — can also learn from the dilemma faced by budding lawyers and physicians.

The first lesson is that quality matters. Most of the lamentation from law-school graduates is coming from those who attended lower-ranked programmes. Although there is ample evidence that the current mechanisms for ranking graduate programmes are limited and problematic, there is nevertheless a high correlation between the overall ranking of a programme and the employment outcomes of its alumni. Therefore, prospective students should shop carefully and ask for real data on the career paths of each programme's graduates. In the United States, tools such as the Grad School Guide (http://graduate-school.phds.org) cast light on the actual quality and outcomes of specific graduate courses. And the US National Academy of Sciences has just released its latest ranking of doctoral programmes (http://sites.nationalacademies.org/pga/resdoc/index.htm).

The second lesson is that debt is important — and this is where the situation for science graduates deviates from that of medical and law students. Although graduate students in the sciences essentially sign themselves up for years of penury in university, nearly all US PhD programmes, and many others around the world, provide stipends for their researchers. PhD students may graduate with few possessions other than a couple of boxes of books and some used Ikea furniture, but at least they do not end up with a huge bill for years of tuition, as law and medical students often do. Frugal science graduate students emerge with a very important life lesson: money does not buy happiness (although it certainly can make misery a lot more comfortable), and living frugally is better than amassing tens of thousands of dollars of debt. Years spent with limited income teach PhD-holding scientists how to be resourceful — and that can be of enormous value throughout a career.

But I believe the most important lesson is that no programme of higher education can guarantee its graduates gainful and lucrative employment. At best, a graduate programme in any discipline can provide its students with key skills, knowledge and abilities. How the graduates apply that learning is up to them.

Broadened horizons
That being said, broader training would help graduates' chances. PhD programmes in the sciences still overemphasize the academic track and actively devalue other career paths. Expanding the PhD experience and preparing holders of scientific doctorates to be successful in a range of careers would not require a major overhaul of graduate programmes. Focused seminars in areas such as communication, business basics and public policy would go a long way towards strengthening the capabilities of PhD students and improving their career prospects. Few academic programmes fully appreciate the true potential that PhD training can confer, or the breadth and depth of value that someone with a PhD can contribute to the world at large; universities often believe that academia is still the most valuable calling for their graduates.

Graduate students and postdocs are in the best position to organize themselves and insist on such professional education as part of their training. After all, they stand to gain the most.

Source: Nature 472, 381 (01 April 2011)

 

[Lê Hải Anh (haianhle)]

Động lực cho phụ nữ làm khoa học, cũng là lời cành báo trước khi quyết định theo đuổi con đường gian nan này .




Women Atop Their Fields Dissect the Scientific Life
By GINA KOLATA

Trích từ The New York Times ngày 6/6/2011

DR. RABIN: [...] I think that the life of a scientist is a fantastic life. I think it is exciting because every day there is something new that you can go and think of. There are challenges, no doubt, and the times when you can’t solve things. So I think it is all a wonderful life. And not to mention even things like time flexibility, traveling around the world, meeting a lot of exciting people. I think that these are fantastic jobs.

DR. APRILE: [...] You have to be very tough, and this is a very hard life and you are always exposed. You have to be extremely strong. You have to face the competition.

DR. HIRSCH: I think the judgment about whether someone should be a scientist or not is a very serious one, because the life of a scientist, whether you are a woman or you are a man, is very difficult. It is a nonstandard life. It is a life with constraints and obligations that don’t come with other types of professions. [...]

DR. APRILE: You have to do what the guys do, and it does not matter what it takes. It is important to be out there, and so it comes with the territory. You have to find a way around to solve the practical problems. You have to.

DR. APRILE: Even if they are not scientists, these daughters of ours, they have had the best example in their life, and they will carry that example and that passion that they see in us, in me and you, with them. And so you never know what will develop along the way. And if they don’t practice science directly, they are going to change the world in other ways. Just because they have had the examples they have.

DR. KING: They will change the world. They don’t have to do it our way.

Background:
Dr. Aprile, a professor of physics at Columbia University, is searching for dark matter.
Dr. Hirsch, a professor of neuroscience at Columbia University, maps brain processes.
Dr. King, a professor of medical genetics at the University of Washington, studies the genetic basis of common complex medical conditions like breast cancer and mental illness.
Dr. Rabin is a cryptography researcher at I.B.M. All four were in New York for the World Science Festival

 

[Lê Hải Anh (haianhle)]

How to improve your writing by overcoming procrastination? The answer is to spend half an hour to write everyday.

"So stop waiting to feel ready. Get started with some short and regular writing snacks. What you write won't be perfect at first, but you will be on your way to becoming a prolific academic writer."​

Turbocharge your writing today

By Maria Gardine & Hugh Kearns

Trích từ: Nature ngày 6/7/2011



As a graduate student, you might find yourself well on the way with your education and 'ABD' (all but dissertation). Day after day, you tell yourself that you really, really intend to start writing your paper. After all, you've collected all the data, analysed them many times and entered them into tables.

But then you start thinking that maybe you need just a few more data. Perhaps, too, you should try a different analysis technique. And what if the tables you used aren't the right ones, or need to be formatted differently?

Many of the thousands of researchers we have worked with are constantly being tripped up by finicky, niggling details that keep them from writing up their research. Every day, they mean to start, but every day, something gets in their way or seems more important — and this can go on for years. Some very common obstacles get in the way of high-quality, high-quantity scholarly writing, but powerful, evidence-based techniques can help researchers to overcome repetitive and unhelpful habits and get moving (see 'How to get out of a dissertation-writing rut').

Box 1: Top tips: How to get out of a dissertation-writing rut

• Write before you feel ready — because you might never feel ready. It's amazing how people magically feel ready when there is an imminent deadline.
• Don't wait to have a clear picture of the paper. As you start putting down your ideas, you may actually clarify them.
• Snack write — work in short, frequent bursts instead of waiting to sit down for big blocks of time. Those blocks hardly ever come, and when they do, they don't usually get used very productively.
• Set specific times in your schedule for writing — don't leave it to chance, because chances are it won't happen.
• Writing means putting new words on the page or substantially rewriting old words. It does not mean editing, reading, referencing or formatting — and it definitely does not mean composing e-mails.
• If you refrain from writing because you worry that what you write won't be good enough, try noting the adage that to write well, you first have to write.
• To really increase the quality and quantity of your writing, get feedback from mentors and colleagues — it can be painful, but it works.

Writing Myths

The biggest impediments to scholarly writing are long-held myths that seem to get passed down through the academic ranks like precious but unhelpful ancient wisdom. The first is the Readiness Myth — “I should write when I feel ready, and I don't feel ready yet”. The secret to high output is that you have to write before you feel ready, because you might never reach that point. Researchers read endlessly and conduct countless experiments in the belief that it will eventually make them feel ready to write — we call these habits readitis and experimentitis. But ironically, all that reading and experimenting often makes them less likely to write, and more confused. So the first way to speed up your writing is to stop waiting, stop reading and experimenting, and start writing. You won't feel ready, but you have to do it anyway.

“Get the words down on the page — no matter how bad you think they look or sound at first.”​

This brings us to the second myth, the Clarity Myth — “I should get it all clear in my head first, and then write it down”. This isn't how writing works in practice. You have probably had the experience in which you were sure about how a paper would go until you started to write it. Then you discovered that there were inconsistencies, or it didn't flow well or the links didn't make sense. This tells you that it wasn't all that coherent in your head, after all. In fact, writing clarifies your thinking. Writing is not recording — you don't just take a photocopy of what is in your head and put it on the page. It is a far more creative and interactive process. As you write, you develop your thoughts. Writing is, in fact, rigorous thinking. So the second way to turbocharge your writing and improve its quality is to get the words down on the page — no matter how bad you think they look or sound at first.​

Snack Writing

Once researchers get beyond the myths that stop them writing, they often declare that they can't possibly write anything eloquent, insightful or clever unless they have a whole day or week to do it in. And because they don't have that amount of time, they conclude that there is no point in starting. We call this 'binge writing'. Binge writing isn't inherently wrong; it's just that, for busy people, it can greatly reduce the amount of writing they do. The alternative is 'snack writing'. This means short — but regular — writing sessions. We suggest about 1–2 hours a day for graduate students who are writing a dissertation, and about 45–90 minutes a day for researchers trying to increase their publication output.


Many researchers tell us that they couldn't possibly get anything useful written in that amount of time. The good news is that studies (which we have replicated many times in practice) show that academics who write for 30 minutes a day produce, on average, more peer-reviewed publications than academics who write for big blocks of time. But the 'snacks' have to be regular — 45 minutes once a week doesn't work, but 45 minutes a day 5 days a week does wonders. When possible, try snack writing first thing in the morning. Our experience suggests that this increases the chances of success by minimizing distractions and ensuring that you have sufficient energy to write clever things. However, for snack writing to lead to really high-quality results, you also need to write in a very specific way.​

What is Writing?

Before we tell you what writing is, we should tell you what it isn't, at least for the purposes of snack writing.

Writing isn't editing: you should not spend your brief snack-writing time trying to find the perfect word or getting your grammar right. Writing isn't reading journal articles for research: write first and read afterwards, so that your writing shows you what you need to read. Writing isn't referencing: when you make that killer argument and want to reference Smith and Brown (2006; or maybe it was 2007?), don't stop and look it up. Write “Smith & Brown (200??)” and keep going. You can look up the reference later. Furthermore, writing is not formatting, literature searching, photocopying, e-mailing or nosing around on Facebook. Writing — at least for your snack-writing sessions — means putting new words on the page or substantially rewriting existing words.

So, you might ask, when do you do all the editing, reading and other associated tasks? The answer is, any time in the other 23 hours and 15 minutes of the day — just not during your snack-writing time.

So stop waiting to feel ready. Get started with some short and regular writing snacks. What you write won't be perfect at first, but you will be on your way to becoming a prolific academic writer.​

Source: Nature 475, 129–130 (2011)

 

[Lê Hải Anh (haianhle)]

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Women in science: In pursuit of female chemists

Carol V. Robinson

Affiliations
Carol V. Robinson is a Royal Society research professor, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK.

As the first female chemistry professor at both the University of Cambridge and the University of Oxford, which have a combined history in chemistry of about 800 years, I am often asked to comment on the poor retention of women chemists by UK universities. The decline from chemistry PhDs (46% women) to professorships (just 6%) is steeper than in other disciplines, including physics and engineering. But numbers don't tell the whole story. Here I offer personal reflections from my career in chemistry about why women leave science.

The greatest attrition occurs during the transition from PhD to research. According to surveys done by the Royal Society of Chemistry in 2000 and 2008, this is when women become discouraged. They find laboratory research in chemistry too adversarial, the difficulties of combining career and family daunting and the lack of role models isolating.

My role model and that of my generation of women chemists is Marie Curie, whose 1911 Nobel Prize in Chemistry we celebrate this year to mark the International Year of Chemistry (she got her first Nobel, in physics, in 1903). Curie was often asked, especially by women, how she could combine family life with a scientific career. Her reply, “it has not been easy”, resonates to this day. A century on from Curie's prize, as a mother of three, it is a question I, too, am often asked. One would hope for greater progress.

I was disappointed to read in a recent survey4 that one-quarter of all 14-years-olds in the United Kingdom confuse Marie Curie with pop singer Mariah Carey. Perhaps we need new role models for today's women? Curie's achievements might be too heroic and the sacrifices she made too great. If so, female chemists, including myself, can offer career narratives that defy the usual stereotypes and, hopefully, inspire others.

Unlike today's generation, I was inspired by Marie Curie's personal life story. Curie, a self-taught chemist, grew up in Warsaw; her father lost his job, forcing her to find work to help support her family. Similarly, my own full-time education ended at age 16 when my father lost his job. Consequently, I didn't follow the usual academic path, but after leaving school became a lab technician at Pfizer Corporation in Sandwich, UK.

Industry was a welcoming environment for me. I was passionately interested in mass spectrometry and began to keep notebooks of observations. My supervisors were impressed and encouraged me to attend night school. After seven years of part-time study and a year's full-time research for a master's degree, I qualified to study for a PhD at the University of Cambridge. At every stage, I felt I had to prove myself and worked hard. With limited PhD funding, I published five papers and wrote my thesis in less than two years.

Shortly after completing my PhD came the challenges of combining family life and career. I chose another unconventional route. I took an eight-year career break to cover the birth of my three children. I was warned that it was highly unlikely I would be able to return to science. I thought this was too high a price to pay for motherhood. Nowadays, when asked to talk to young women, I am often asked not to mention my career break, although I usually do. Sadly, it is not something that many institutions encourage.

You can have it all

Is the choice between children — and a normal family life — and becoming a professional scientist really so stark? I asked Ada Yonath, the only living female Nobel laureate in chemistry, how she balanced the demands of family and science. She replied that it is possible as long as you have a passion for both. I agree — we have to change the notion that academic jobs cannot be family friendly.

Admittedly, after my eight-year absence, it was hard to find a position in science. I had three interviews before convincing a panel that I was committed (one interviewer remembered me positively from my student days). It also wasn't easy being a postdoc when my children were school-age, but I was immensely productive in the morning. From about 5 a.m. my thoughts were clear. I had no interruptions and no guilt. As my children got older, I began to attend international meetings, often taking the children with me, even into the lecture hall. These sorts of opportunities to mix family and professional life are unparalleled in many other professions.

My research may also have benefited from having a career break. On returning in 1992, well-meaning academics tried to persuade me to follow fashionable pathways in proteomics and, a few years later, in metabolomics. But becoming a principal investigator in my forties, much later than most, I was already several years behind the leading labs and not sufficiently excited by these trends. I needed to do something different.

“Women don't need to adopt more 'male' character traits to succeed.”

“Nothing in life is to be feared, it is only to be understood,” is my favourite quote from Curie, who, during her discovery of radioactivity, unknowingly exposed herself to great personal danger in her pursuit of the unknown. Fearlessness is one quality I have noticed among many successful chemists, men and women. Yonath did not take on easy projects and was regularly accused of being 'a dreamer'.

In my own lab, I pursued a path of putting macromolecular complexes into the gas phase of a mass spectrometer, not an obvious choice for the structural-biology questions I intended to ask. Well-respected scientists told me that the results would be meaningless. Happily, I chose not to follow too much of this advice. I might have been less brave had I been younger and more eager to please.

Chemistry has a reputation for being more cut-throat than biology or physics5. It has a macho culture in which getting to the finish line first is more important than how you get there. And women are assumed to be less competitive than men. There is some truth in this. Too often, female scientists shy away from responsible roles or don't have sufficient confidence or aspirations.

Culture reinforcement

Certainly, we can't blame men alone for creating a male-dominated environment when women scientists are often too keen to be invisible, or worse, to become honorary males, by adopting aggressive communication styles, say, or eschewing any interest in appearance. Curie herself proudly claimed that she had no dresses save the black one she wore every day to the laboratory. When I started at the University of Cambridge, I was advised not to dress so well by a female colleague, who warned I would be confused with the secretarial staff. Another colleague confessed to hiding shopping bags for fear of being considered too vain. But by behaving or dressing as honorary men, we only reinforce the macho culture of chemistry.

Consider how off-putting that might be to the younger generation. Let's start with our own daughters. “Would you advise them to go into science?” was a question recently posed to a small group of top American women scientists6. “Only if she is made of steel,” was the consensus. I don't agree. I would have been very happy for my only daughter, a mathematician, to have been a chemist. I am proud of a mother–daughter publication resulting from her holiday research in my lab. Women don't need to adopt more 'male' character traits to succeed.

Today, 11 of the 20 people in my lab are women. I didn't set out to make it this way. I think women are drawn to the group, believing that I am likely to understand the conflicting demands of family and career. I am particularly proud of the many successful young women with families whom I have mentored, but I don't feel that I am doing anything special. I simply treat everyone as I would like to be treated myself — supported and nurtured. Perhaps all we can do is to change attitudes one research group at a time.

We must also challenge the patronizing cultural stereotypes that deter women. Headlines such as “Oxford housewife wins Nobel” and “One giant leap for womankind — and Israel” (for Nobel laureates Dorothy Hodgkin and Yonath, respectively) are par for the course. “Mother wins prize” and “Woman wins top science prize”, are both newspaper headlines reporting my more modest achievements. The Rosalind Franklin award in 2004, from the Royal Society, came with a significant sum described as “a lot of money to spend on shoes”. I confess to a weakness for shoes. But I in fact set up a fund to support visiting female lecturers and to establish a mentoring scheme for female postgraduates at Cambridge.

Attitudes to women in science have improved, but there is still some way to go. Yonath remembers a time when a visitor to her lab commented that her research was “so good that he thought it likely carried out by a man”. As a junior researcher, I was asked many times “who is the senior man you work for?”. Today, female postgraduates note less explicit biases that can make them feel excluded: from the all-male photos in chemistry departments, to the timing of early evening seminars, and the ensuing discussions in the local pub. So, we must all do more to support female chemists: by speaking out at injustice or prejudice, instead of staying quiet, and by encouraging talented colleagues to aspire to more demanding roles.

Curie encouraged her elder daughter to follow in her footsteps. Irène Joliot-Curie received the second Nobel prize awarded to a woman in chemistry. As Marie Curie's granddaughter (herself a respected nuclear physicist) said: “We have to change the mentality that men are better scientists.” Our daughters and granddaughters deserve nothing less.

Source: Nature 476, 273–275 (18 August 2011)