Posts about research paper

H-index Rank for Countries: for Science Publications

The SCImago Journal and Country Rank provides journal and country scientific indicators. As stated in previous posts, these types of rankings have limitations but they are also interesting. The table shows the top 6 countries by h-index and then some others I chose to list (the top 6 repeat from my post in 2008 – Country H-index Rank for Science Publications). The h-index provides a numeric indication of scientific production and significance (by looking at the citations given papers by other papers). Read more about the h-index (Hirsh index).

Country h-index h-index (2007) % of World
Population
total Cites
USA

1,139 793     4.5% 87,296,701
United Kingdom

689 465     .9% 21,030,171
Germany

607 408     1.2% 17,576,464
France

554 376     1.0% 12,168,898
Canada

536 370     .5% 10,375,245
Japan

527 372     1.8% 14,341,252
Additional countries of interest
18) China

279 161 19.4% 5,614,294
21) South Korea

258 161     .7% 2,710,566
22) Brazil

239 148  2.8% 1,970,704
25) India

227 146 17.5% 2,590,791
31) Singapore

196 .01% 871,512

Related: Top Countries for Science and Math Education: Finland, Hong Kong and KoreaWorldwide Science and Engineering Doctoral Degree Data Top 15 Manufacturing Countries in 2009Science and Engineering Doctoral Degrees WorldwideRanking Universities Worldwide (2008)Government Debt as Percentage of GDP 1990-2009: USA, Japan, Germany, China…

Smokers with High Blood Pressure and High Cholesterol Lose 10 Years

By examining data from the Whitehall Study researchers have found smokers with high blood pressure and high cholesterol in middle age died 10 years earlier than the others after reaching age 50. This is independent of changes after later in life (quiting smoking, etc.). Life expectancy in relation to cardiovascular risk factors: 38 year follow-up of 19,000 men in the Whitehall study

At entry, 42% of the men were current smokers, 39% had high blood pressure, and 51% had high cholesterol. At the re-examination, about two thirds of the previously “current” smokers had quit smoking shortly after entry and the mean differences in levels of those with high and low levels of blood pressure and cholesterol were attenuated by two thirds. Compared with men without any baseline risk factors, the presence of all three risk factors at entry was associated with a 10 year shorter life expectancy from age 50 (23.7 v 33.3 years). Compared with men in the lowest 5% of a risk score based on smoking, diabetes, employment grade, and continuous levels of blood pressure, cholesterol concentration, and body mass index (BMI), men in the highest 5% had a 15 year shorter life expectancy from age 50 (20.2 v 35.4 years).

Conclusion Despite substantial changes in these risk factors over time, baseline differences in risk factors were associated with 10 to 15 year shorter life expectancy from age 50.

Another conclusion: if you don’t want to live a shorter life, don’t smoke. Not a new idea but given how many people continue to smoke it seems some don’t understand this conclusion.

Related: Global Cancer Deaths to Double by 2030Leading Causes of Deathmore posts on open access papersStudy Finds Obesity as Teen as Deadly as Smoking

Fat Cell Count Set in Childhood

Fat cell number is set in childhood and stays constant in adulthood

As fat people have an abundance of fat tissue, the natural assumption is that fat people have more fat cells, or ‘adipocytes’. That’s only part of the story – it turns out that overweight and obese people not only have a surplus of fat cells, they have larger ones too.

During adulthood, about 8% of fat cells die every year only to be replaced by new ones. As a result, adults have a constant number of fat cells, even those who lose masses of weight. Instead, it’s changes in the volume of fat cells that causes body weight to rise and fall.

we couldn’t have a clearer indication of the importance of childhood as a window for preventing obesity and the chronic diseases affected by it – cancer, heart disease, diabetes and more.

The message is especially stark following the recent Foresight report, which estimated that if current trends are left unchecked, by 2050 a quarter of all UK children under the age of 16 will be obese. The knowledge that their fat cell count will then be set for life makes the cost of inaction even higher. Fortunately, it seems that the UK Government is taking appropriate steps and recently pledged over a third of a billion pounds on a concerted strategy to tackle childhood obesity.

Related: $500 Million to Reduce Childhood Obesity in USAObesity Epidemic Explained – Kind OfDrinking Soda and Obesity

Eating Breakfast Keeps Teenagers Leaner

Breakfast ‘keeps teenagers lean’

In a five year study of more than 2,000 youngsters, those who skipped breakfast weighed on average 5lbs (2.3kg) more than those who ate first thing. This was despite the fact that the breakfast-eaters consumed more calories in the course of the day. But the study in Pediatrics found they were likely to be much more active.

The University of Minnesota research adds weight to a growing body of evidence that those who eat breakfast – whether young or old – are leaner than those who do not.

“The real problem is the profusion of messages about obesity. We need to make clear that eating regular meals is vital – and that a proper breakfast is very important. “If you eat well first thing, you’ll feel brighter, you’ll have more get up and go – and that will mean you’ll expend more energy.”

Teenagers are not the only ones who may benefit from sitting down to a proper breakfast. In a study of nearly 7,000 middle-aged people in Norfolk, a team from Cambridge University found that those who ate the most in the morning put on the least amount of weight.

Related: Breakfast Eating and Weight Change in a 5-Year Prospective Analysis of Adolescents: Project EAT (Eating Among Teens)$500 Million to Reduce Childhood Obesity in USAEat food. Not too much. Mostly plantsFood Health Policy Blog

Explaining the Missing Antimatter

Flipping particle could explain missing antimatter

It is one the biggest mysteries in physics – where did all the antimatter go? Now a team of physicists claims to have found the first ever hint of an answer in experimental data. The findings could signal a major crack in the standard model, the theoretical edifice that describes nature’s fundamental particles and forces.

In its early days, the cosmos was a cauldron of radiation and equal amounts of matter and antimatter. As it cooled, all the antimatter annihilated in collisions with matter – but for some reason the proportions ended up lopsided, leaving some of the matter intact.

Physicists think the explanation for this lies with the weak nuclear force, which differs from the other fundamental forces in that it does not act equally on matter and antimatter. This asymmetry, called CP violation, could have allowed the matter to survive to form the elements, stars and galaxies we see today.

“It is tantalisingly interesting at the moment,” says Val Gibson, an expert on B meson physics at the University of Cambridge. “If it is true, it is earth-shattering.” Jacobo Konigsberg, who leads the CDF collaboration, says that Tevatron researchers are “cautiously excited” about the analysis. He points out that more data needs to be analysed to rule out a statistical fluke, which has happened several times before in particle physics.

Related: First Evidence of New Physics in b <--> s Transitions (research paper)posts tagged physicsMatter to Anti-Matter 3 Trillion Times a SecondQuantum Mechanics Made Relatively Simple Podcasts

Laws of Physics May Need a Revision

Something seems wrong with the laws of physics

Einstein’s general theory of relativity swept Newton away by showing that gravity operates by distorting space itself.

Even Einstein, however, may not have got it right. Modern instruments have shown a departure from his predictions, too. In 1990 mission controllers at the Jet Propulsion Laboratory (JPL) in Pasadena, California, which operates America’s unmanned interplanetary space probes, noticed something odd happen to a Jupiter-bound craft, called Galileo. As it was flung around the Earth in what is known as a slingshot manoeuvre (designed to speed it on its way to the outer solar system), Galileo picked up more velocity than expected. Not much. Four millimetres a second, to be precise. But well within the range that can reliably be detected.

Altogether, John Anderson and his colleagues analysed six slingshots involving five different spacecraft. Their paper on the matter is about to be published in Physical Review Letters. Crucially for the idea that there really is a systematic flaw in the laws of physics as they are understood today, their data can be described by a simple formula. It is therefore possible to predict what should happen on future occasions.

That is what Dr Anderson and his team have now done. They have worked out the exact amount of extra speed that should be observed when they analyse the data from a slingshot last November, which involved a craft called Rosetta. If their prediction is correct, it will confirm that the phenomenon is real and that their formula is capturing its essence. Although the cause would remain unknown, a likely explanation is that something in the laws of gravity needs radical revision.

An interesting puzzle that illustrates how scientists attempt to confirm our understanding and real world results. And those efforts include uncertainty and confusion. Too often, I think, people think science is only about absolute truth and facts without any room for questions. We understand gravity well, but that does not mean we have no mysteries yet to solve about gravity.

Research paper: The Anomalous Trajectories of the Pioneer Spacecraft

Related: NASA Baffled by Unexplained Force Acting on Space ProbesMysterious Effect May Influence Spacecraft TrajectoriesEarth’s rotation may account for wayward spacecraftPioneer anomaly put to the testUnderstanding EvolutionScientists Search for Clues To Bee Mystery

Electron Filmed for the First Time

Photo of electron movement

Now it is possible to see a movie of an electron. The movie shows how an electron rides on a light wave after just having been pulled away from an atom. This is the first time an electron has ever been filmed. Previously it has been impossible to photograph electrons since their extremely high velocities have produced blurry pictures. In order to capture these rapid events, extremely short flashes of light are necessary, but such flashes were not previously available.

With the use of a newly developed technology for generating short pulses from intense laser light, so-called attosecond pulses, scientists at the Lund University Faculty of Engineering in Sweden have managed to capture the electron motion for the first time. “It takes about 150 attoseconds for an electron to circle the nucleus of an atom. An attosecond is 10-18 seconds long, or, expressed in another way: an attosecond is related to a second as a second is related to the age of the universe,” says Johan Mauritsson, an assistant professor in atomic physics at the Faculty of Engineering, Lund University.

Scientists also hope to find out more about what happens with the rest of the atom when an inner electron leaves it, for instance how and when the other electrons fill in the gap that is created. “What we are doing is pure basic research. If there happen to be future applications, they will have to be seen as a bonus,” adds Johan Mauritsson. The length of the film corresponds to a single oscillation of the light, but the speed has then been ratcheted down considerably so that we can watch it. The filmed sequence shows the energy distribution of the electron and is therefore not a film in the usual sense.

Photo: Experimental results obtained in helium at an intensity of 1:2 x 1013 W=c/m2 are shown. The results are
distinctively different from those taken in argon (Fig. 1).With this higher intensity, more momentum is transferred to the electrons, and in combination with the lower initial energy, some electrons return to the atomic potential for further interaction. In the first panel, we compare the experimental results (right) with theoretical calculations (left) obtained for the same conditions.
Continue reading

The Science of Kissing

The Differences in Gender — Sealed With a Kiss

In people, kissing to express affection is almost universal. About 90 percent of human cultures do it. One traditional view is that kissing, known scientifically as osculation, evolved from women chewing food for their children and giving it to them mouth-to-mouth, Fisher said.

But, she said, “I’ve never believed that,” adding that similar behavior is found in many species. Birds tap beaks. Elephants shove their trunks in each other’s mouths. Primates called bonobos practice their own version of French kissing. Fisher believes kissing is all about choosing the right mate.

“There’s so much information exchanged when you kiss someone that I just thought it must play a vital role in mate choice, and this paper is elegantly showing that,” Fisher said. A disproportionate amount of the brain, she noted, is geared toward interpreting signals from the mouth.

The research paper – Sex Differences in Romantic Kissing Among College Students: An Evolutionary Perspective

Related: The Psychobiology of Romantic KissingSexy MathSummer Camp Psychology Experiment

In Tunguska, Siberia 99 Years Ago

Just What Happened 99 Years Ago in Tunguska, Siberia?

in the morning of 30 June 1908, a few native peoples in Siberia reported seeing a blue light in the sky that was as bright as the sun and hearing a series of loud explosions, accompanied by fierce winds and fire. These explosions, which flattened the pristine Siberian Taiga for 770 miles (2,000 kilometers) around, are estimated to have had the power of 2000 Hiroshima atomic bombs. However, this area is so remote and Russia was experiencing so much political turmoil that no one was able to investigate the scene until 1927

Gasperini’s team says their data suggest that a 10 meter (33 foot) wide fragment of the celestial object was blasted free by the explosion and continued traveling in the same direction that the original object was moving in. This fragment traveled slowly, about 1 kilometer a second (0.6 mile) per second. When the fragment plowed into the marshy terrain five miles north of the explosion epicenter, it created a long, trenchlike depression.

“It splashed on the soft, swampy soil and melted the underlying permafrost layer, releasing CO2 [carbon dioxide], water vapor, and methane that broadened the hole, hence the shape and size of the basin, unusual for an impact crater,” argues Gasperini, adding that “our hypothesis is the only one that accounts for the funnel-like morphology of Lake Cheko’s bottom.”

Related: research paper A possible impact crater for the 1908 Tunguska EventMeteorite, Older than the Sun, Found in CanadaNASA Tests Robots at Meteor Crater

Evolution of Antibiotic Resistance

Inhibition of Mutation and Combating the Evolution of Antibiotic Resistance from the Public Library of Science Biology Journal:

The emergence of drug-resistant bacteria poses a serious threat to human health. In the case of several antibiotics, including those of the quinolone and rifamycin classes, bacteria rapidly acquire resistance through mutation of chromosomal genes during therapy. In this work, we show that preventing induction of the SOS response by interfering with the activity of the protease LexA renders pathogenic Escherichia coli unable to evolve resistance in vivo to ciprofloxacin or rifampicin, important quinolone and rifamycin antibiotics. We show in vitro that LexA cleavage is induced during RecBC-mediated repair of ciprofloxacin-mediated DNA damage and that this results in the derepression of the SOS-regulated polymerases Pol II, Pol IV and Pol V, which collaborate to induce resistance-conferring mutations. Our findings indicate that the inhibition of mutation could serve as a novel therapeutic strategy to combat the evolution of antibiotic resistance.