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Post n°7 pubblicato il 11 Novembre 2010 da xueji
Perspective: Put Integrity High on Your To-Do List When the active consideration of integrity is put off to another day, it becomes easier to take the first compromising steps toward irresponsible research practices. -- Nicholas Steneck For many researchers, integrity is akin to a note on a cluttered reminder board. They know it's important, but other reminders -- to run experiments, apply for grants, write papers, and so on -- take precedence. Serious thinking about research integrity gets put off to another day. If all researchers set high standards for responsible behavior in research, it might not be so important to pay attention to integrity. Unfortunately, more than a few do not, and the behavior of those who are willing to bend and sometimes deliberately break the rules can impact even the most principled researcher. Consequently, anyone who places integrity at the bottom of a to-do list does so at some personal risk. When integrity is addressed, the focus is usually on the worst cases of misbehavior, commonly referred to as "research misconduct." The U.S. government defines research misconduct as "fabrication, falsification, and plagiarism." Allegations of research misconduct can end careers and cost institutions time and money. Misconduct cases can also create difficult personal situations. What would you do if you were co-author on a paper that had to be retracted because one of the other co-authors engaged in misconduct? Would you list the paper on your resumé to get credit for legitimate work you did, or would you take it off to avoid being associated with a misconduct case? How would your career be affected if a mentor's or collaborator's grant ended due to a misconduct finding? Research misconduct impacts the careers of both perpetrators and bystanders. Misconduct is not, however, the first or even the most important test of integrity in scientific practice. More significant by far are the dozens of routine decisions scientists make every day. The relevance to integrity of these small choices may not be apparent. As small decisions, their consequences are not obvious, which makes it easier to justify bending rules and cutting corners: What difference would it make if you described essentially the same research results in more than one publication without proper notification, added a few references in your notes that may or may not actually support your research, or used a few sentences from someone else's methods section to describe what you have done? When the active consideration of integrity is put off to another day, it becomes easier to take the first compromising steps toward irresponsible research practices. For beginning researchers, decisions about authorship and publication are usually the first to raise questions about proper and improper behavior. What qualifies someone to be an author of a research publication? When is it necessary to credit others for words and work used in your paper? Do different attribution standards apply to different parts of papers, such as the methods section versus the discussion section? Can you reuse your own words without engaging in self-plagiarism? The point of this article is not to provide answers; it is, rather, to emphasize to beginning researchers the importance of studying the standards of research practice in their areas of investigation. Researchers who start research projects without knowing the answers run the risk of making mistakes and getting into difficult situations. So, here are the first two items that should be on every scientist's integrity to-do list: 1. Fully understand the rules of authorship and credit that apply to your research. 2. Don't begin a research project until everyone involved agrees who will be listed as an author and in what order. Laboratory management -- especially record keeping -- is another area in which researchers can easily get into trouble. Researchers have a responsibility to be good stewards of research funds, to keep meticulous records of the science done in the lab (i.e., keep complete lab notebooks, whether paper or electronic), and to comply with ethics and other regulations. ( See Box ). Studies suggest that one in three researchers fails to keep proper laboratory records. Irresponsible laboratory practices waste time and funds. They also harm careers when experiments have to be rerun, results cannot be replicated, and papers must be retracted. You can lose your claim to intellectual property if you cannot document when and how something was discovered. Misconduct can go undetected when colleagues fail to keep track of what is going on in their laboratories. Entire university research programs can be suspended if informed consent for a few projects is not properly documented. To avoid these and other improper laboratory-management practices, two more items should be on every scientist's integrity to-do list: 3. Take note of and understand the rules and regulations that apply to your research. Use them to guide your day-to-day decisions. 4. Develop a system or routine for reviewing how well you are doing in meeting your laboratory-management responsibilities. Integrity is judged by what you do, not what you intended to do.
Post n°6 pubblicato il 05 Novembre 2010 da xueji
 Brain Zaps Improve Numbers game. In a new study, volunteers learned to ascribe value to strange symbols, such as the ones shown here. Credit: Adapted from Kadosh et al., Current Biology, 20 (23 November 2010) Need to improve your math skills or do your taxes faster? Try zapping your brain with electricity. Researchers have shown that administering a small electrical charge to the brain may enhance a person's ability to process numbers for up to 6 months. The team says the approach, which it claims is harmless, could one day restore numerical skills in people suffering from degenerative diseases or stroke, and it may even improve the math abilities of the general population. The brain's math center appears to be the right side of the parietal lobe, a region that sits beneath the crown of the head. People with injuries to this region have difficulty counting, and it's unusually active in young children learning their 1, 2, 3s. Those findings made Roi Cohen Kadosh, a cognitive neuroscientist at the University of Oxford in the United Kingdom, wonder if stimulating this part of the brain could improve a person's ability to manipulate numbers. Cohen Kadosh and colleagues recruited 15 university students and trained them to learn the value of nine made-up symbols, including shapes that looked like triangles and staples (see picture). To replicate what children go through when they first learn numbers, the researchers presented the volunteers with two symbols at a time and asked them which one had a higher value. At first, the volunteers had to guess, because they had never seen the symbols before. But as the training progressed, those volunteers who remembered their correct guesses began to learn the relative value of all nine symbols. During 6 days of training, the researchers passed electrical currents into the volunteers' brains. Using a technique called transcranial direct current stimulation (TDCS), the team attached electrodes to the scalps of the volunteers—over the right side of the parietal lobe—and applied a weak electrical current. Each day, five volunteers received a positive current for 20 minutes; five volunteers received a negative current for 20 minutes; and five volunteers received a positive current for 30 seconds. The volunteers usually report just a "tingling sensation" around the electrodes on the scalp, says Cohen Kadosh, who says that he tried out the procedure on himself before subjecting anyone else to it. Each training day ended with a type of test known as a numerical Stroop task. In the classic version of the test, volunteers are shown, say, the word "blue" written in red ink and asked to state the color of the ink. Most of us hesitate for a second because we have good reading skills and want to say what we've read—i.e., "blue." (You can try the test for yourself here.) In Cohen Kadosh's version of the test, the volunteers were asked to look at the symbols they had learned—except this time, some of the low-value symbols were written larger than the high-value symbols—and say which of the symbols was larger in size. Students who hesitated were judged to have learned the symbols better than those who did not hesitate. Volunteers who had received 20 minutes of positive electric current to their brains per day performed best on the test, the team reports online today in Current Biology. Specifically, they hesitated about twice as long as the group that received only 30 seconds of positive current. Students in the group that received 20 minutes of negative current per day were unable to recognize the symbols at all and didn't respond. The effects of the electrical treatment were retained even 6 months later. In addition to improving peoples' numerical skills, electrically stimulating the brain could help patients recover word recognition and motor control after strokes, speculates Cohen Kadosh. And he adds that he sees no reason why this approach can't be used to enhance word and numbers skills in people with normal math or language ability. Silke Göbel, a psychologist at the University of York in the United Kingdom, cautions that although the people treated with TDCS may have altered reactions on the Stroop test, the research team has not yet directly shown this improves real-world math skills. "It is not clear whether this effect is really specific to number learning or would generalize to any new stimuli, ... [but] this is obviously an important question for future studies", she says.
Post n°5 pubblicato il 03 Novembre 2010 da xueji
Why Saturn's B Ring Looks Like a Vinyl Record Grooviness explained. Saturn's B ring (bright central band in Saturn image) is heavily "grooved" (brightest banding, above) by the innate tendency of densely packed ring particles to pack together even more densely. Credit: Cassini Imaging Team/SSI/JPL/ESA/NASA; (inset) NASA/JPL/Space Science Institute For 3 decades, Saturn's broadest, brightest, and most massive ring has also been its most mysterious. The B ring is etched with darker "grooves," giving it the appearance of an old-time vinyl phonograph record. But no one could see what might be doing the etching. Now researchers see signs that the grooves are due not to outside forces but to a natural tendency of the densest parts of rings to clump into denser, brighter bands. Similar clumping is probably at work shaping galaxies and nascent planetary systems. Astronomers have long known about processes that shaped Saturn's other rings. Imaging by the Voyager 1 and 2 spacecrafts in the late 1970s had shown how the gravity of distant moons and nearby moonlets can sculpt the planet's vanishingly thin swarm of trillions of orbiting icy bits into four main rings—and within them thousands of ringlets, ring gaps, and spiraling waves. But the B ring remained an enigma. No one could find any orbiting bodies that would gravitationally cut grooves across the 7.5-million-kilometer breadth of the B ring, which, like the rest of the rings, is at most a few tens of meters thick. Part of the problem was that astronomers didn't have enough data on the B ring. Previous studies focused on a mere few days of observations by the Voyagers, but Joseph Spitale and Carolyn Porco took a much longer look. In a paper published this week in The Astronomical Journal, the pair of ring dynamicists at the Space Science Institute in Boulder, Colorado, studied 4 years of observations from the orbiting Cassini spacecraft. They identified three subtle rhythmic pulsations in the position of the B ring's outer edge. The oscillations carry the edge in and out by about 75 kilometers with the same timing, predicted a long-hypothesized mechanism called "overstability." Overstability can occur in the densely packed B ring, and only there, because particles there are so close together that they behave collectively more like a liquid than like a gas, says Spitale. Random disturbances nudging them even closer can then set off waves of densely packed ring particles with the same frequencies that Spitale and Porco see at the ring's edge. Gentle collisions of ring particles then amplify these waves until they are powerful enough to show up as pulsations in the B-ring edge. The same spontaneously generated waves are likely creating the grooved appearance seen across the B ring, says Spitale. The process could also be shaping spiral galaxies and disks of dust and gas-forming planets around other stars, although making the leap to such grand scales would be difficult. The Cassini discovery "shows that even in a simple system you can get remarkable behavior," says physicist Peter Goldreich of the California Institute of Technology in Pasadena. "This is going to lead to a lot more understanding about rings."
Post n°4 pubblicato il 01 Novembre 2010 da xueji
登入為:我的新 JS-Kit 帳號我的 Google 個人資料我的 Twitter 帳號我的 FriendFeed 帳號我的 Yahoo! 帳號我的 Blogger 帳號我的 JS-Kit 帳號我的 Haloscan 帳號我的 OpenID  NIH Scientists See Crackdown on Consulting as Too Restrictive Five years ago after a scandal erupted over employees who were consulting for drug companies, the National Institutes of Health (NIH) banned most such relationships by in-house scientists. A new study finds mixed effects. The rules apparently haven't hindered scientific productivity, the survey finds. But a whopping 80% of NIH scientists find the rules too restrictive, and many say they have hampered the agency's ability to recruit new faculty members. NIH banned most industry consulting by its staff members after a newspaper investigation found that some senior researchers were earning large sums of money from companies. Intramural scientists warned that the strict rules would drive staff away. Darren Zinner of Brandeis University, Eric Campbell of Massachusetts General Hospital, and colleagues have now published the first peer-reviewed study on the rules' impact. It is based on a survey from October 2008 through January 2009 sent to 900 senior investigators and administrators; 70% responded. Not surprisingly, industrial ties are now fewer—only about 33% reported an industry relationship, down from about half before the 2005 rules. This hasn't affected the average researcher's output of papers and patent applications, the survey finds. And nearly half of those surveyed say the new rules have improved NIH's public image. But 80% say the rules are too stringent, 77% think it is now harder to accomplish NIH's mission, and 66% are less satisfied with their jobs. More than half of researchers and 78% of administrators said the rules have made it harder to recruit new faculty members. Although NIH may have gained public credibility, the rules "also made it more difficult for the organization to complete its mission," the authors of the study conclude in the November issue of Academic Medicine. NIH officials put a positive slant on the study in an accompanying commentary. Interactions with industry "have continued relatively unaffected," writes Michael Gottesman, NIH deputy director for intramural research, and NIH ethics officer Holli Beckerman Jaffe. They point to trends in new cooperative agreements between NIH researchers and companies (known as CRADAs), which, after dropping in 2006, have risen to previous levels of more than 30 per year. Yet the rules, they acknowledge, "have challenged NIH's ability to attract and retain some of the most qualified scientists." NIH is now preparing to tighten the rules for extramural scientists as well, watching outside consulting in particular—although mainly by asking researchers to report more information to NIH and their institutions. The planned changes would not restrict what grant recipients can do as long as potential conflicts of interest are reviewed and managed. Interestingly, despite their unhappiness with the much tighter rules at NIH, two-thirds of the
Post n°3 pubblicato il 30 Ottobre 2010 da xueji
Hellish 'Super-Earths' Likely Prevalent Throughout Our Galaxy Planet hunter. The Earth-orbiting, French-built COROT space telescope has been looking for the transits of certain Earth-like planets since 2006. Credit: Illustration by D. Ducros/CNES 2006; (inset)LESIA/OBSPM Although it's only a little bigger than Earth and is made of the same ingredients, this planet is no paradise. It orbits so close to its parent star that its surface is a sea of molten lava, its atmosphere swirling with silicate vapor. The galaxy is rife with hellish worlds like this one, astronomers now predict based on theoretical studies. New findings suggest that Earth-like planets are common throughout the galaxy. However, when Kevin Schlaufman, a graduate student at the University of California, Santa Cruz, and colleagues used computer models to simulate a theoretical extrasolar planet population, they found that a new breed of super-Earths was also surprisingly prevalent. The team's results, to be published in The Astrophysical Journal Letters, indicate that these rocky planets would range up to 10 times the mass of Earth and would orbit their host stars in 24 hours or less, as does the planet described here. "If our model and analysis are correct, these very hot super-Earths would be the hottest planets in the galaxy," says Schlaufman. "Their surfaces would likely be oceans of lava, possibly in the process of being vaporized by their own stars." Such planets typically form early in the history of a solar system and are farther away from their stars than Earth is from the sun. So how does an Earth-mass planet end up so close to its parent star? The short answer is via inward migration. Over about 100,000 years, the planets interact with their surrounding, gas-rich planetary disks, causing their orbits to swiftly move inward toward their parent stars. Schlaufman notes that life on these scorching planets is totally out of the question. Natalie Batalha, the deputy science team lead for NASA's Kepler mission to find Earth-like worlds, says that Kepler's detection of many planetary candidates smaller than Neptune in close orbits around their stars suggests that Schlaufman and colleagues' models "might be right on target." And the project is expected to announce the discovery of a slew of such hot super-Earths by early next year. "Such super-Earths would be different from anything in our solar system," said Eric Ford, an astronomer at the University of Florida, Gainesville, who was not involved in the study. "One side is continuously illuminated and scorching hot, while the other side remains in perpetual night." And conditions will only get worse. Schlaufman says that the same effects that cause tides on Earth also force very hot super-Earths to begin death spirals into their parent stars. The side of the planet not facing the star will be pulled in one direction, and the side of the planet facing the star will be pulled in another, says Schlaufman. Eventually, before being incinerated, the super-Earth will be ripped apart.
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