Category Archives: Science

Amazing Webcast of the Aurora Borealis

The Aurora from Terje Sorgjerd on Vimeo.

Norwegian landscape photographer Terje Sorgjerd spent a week capturing one of the biggest aurora borealis shows in recent years. He shot the video in and around Kirkenes and Pas National Park bordering Russia at temperatures around -25 Celsius.

Aurora are caused by the collision of charged particles and the Earth’s magnetic field. Aurora Borealis is Latin for northern lights. An aurora is usually observed at night and typically occurs in the ionosphere. The lights are commonly visible between 60 and 72 degrees north and south latitudes, which place them in a ring just within the Arctic and Antarctic polar circles.

Auroras result from emissions of photons in the Earth’s upper atmosphere, above 80 km (50 miles), from ionized nitrogen atoms regaining an electron, and oxygen and nitrogen atoms returning from an excited state to ground state. They are ionized or excited by the collision of solar wind particles being funneled down and accelerated along the Earth’s magnetic field lines; excitation energy is lost by the emission of a photon of light, or by collision with another atom or molecule. Oxygen emissions give off a green or reddish hue, depending on the amount of energy. Nitrogen emissions give off a blue (if the atom regains and electron after it has been ionized) or red hue (if returning to the ground state from an excited state).

Auroras are associated with the solar wind, a flow of ions continuously flowing outward from the Sun. The Earth’s magnetic field traps these particles, many of which travel toward the poles where they are accelerated toward Earth. Collisions between these ions and atmospheric atoms and molecules cause energy releases in the form of auroras appearing in large circles around the poles. Auroras are more frequent and brighter during the intense phase of the solar cycle when coronal mass ejections increase the intensity of the solar wind.

Ten Things Everyone Should Know About Science

As the writer of this blog (which is located at engineering.curiouscatblog.net) I am a strong believer in the importance of scientific literacy. Neil Degrasse Tyson stated the importance very well, as I mentioned in a previous post, the scientifically literate see a different world

If you are scientifically literate the world looks very different to you. Its not just a lot of mysterious things happening. There is a lot we understand out there. And that understanding empowers you to, first, not be taken advantage of by others who do understand it. And second there are issues that confront society that have science as their foundation. If you are scientifically illiterate, in a way, you are disenfranchising yourself from the democratic process, and you don’t even know it.

The Financial Times has complied a list of the 10 things everyone should know about science

Evolution – previous posts: Evolution is Fundamental to Science – posts tagged: evolution
Genes and DNA – tags: genes – genetics – DNA – RNA
Big bang – tags: physics, posts mentioning big bang
Relativity – General Relativity Einstein/Essen Anniversary Test – posts mentioning relativity
Quantum mechanics – Quantum Mechanics Made Relatively Simple Podcasts, Quantum mechanics
Radiation
Atoms and nuclear reactions
Molecules and chemical reactions – posts on chemistry
Digital data – I must admit, even reading their comments, I don’t understand what they are thinking here. There certainly is a great deal of digital data and the future certainly going to involve a great deal more, but this just doesn’t fit, in my opinion.
Statistical significance – Seeing Patterns Where None Exists, Statistics Insights for Scientists and Engineers, Correlation is Not Causation post on statistics – experimentation

It is a challenge to create such a list. I agree with most of what they have. I would like to look at changing the last 2 and radiation, though. I would probably include something about the scientific method rather than statistical significance. Another area I would consider is something about bacteria and/or viruses. You can maybe include them under genes, but viruses and bacteria are amazing in the very strange things they do with genes and I think that is worthy of its own item. Another possibility is thinking of separating out a second spot for things related to the scientific method – causation, randomized testing, multivariate experiments… I would also consider one, or more of the following or something related to them biology – chlorophyll, the the life of bacteria in our bodies, something related to human health (how drugs work, medical studies…), etc..

The Ten Things Everyone Should Know About Science

Evolution through natural selection remains as valid today as it was 150 years ago when expressed with great elegance by Charles Darwin in The Origin of Species. The mechanism of evolution depends on the fact that tiny hereditable changes take place the whole time in all organisms, from microbes to people.
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An important feature of Darwinian evolution is that it operates at the level of the individual. There is no mechanism for natural selection to change the species as a whole, other than through the accumulation of changes that lead to the survival of the fittest individuals.

The rate of evolution varies enormously between different types of organism and different environmental circumstances. It can proceed very quickly when the pressure is great, as, for example, with bacteria exposed to antibiotics, when drug-resistant mutations may arise and spread through the bacterial population within months.

Why does it matter? Evolution is coming under renewed assault, particularly in the US, from fundamentalist Christians who want creationism to be taught in schools. Although evolution has had virtually unanimous support from professional scientists for at least a century, polls show that American public opinion still favours creationism.

Diet May Help ADHD Kids More Than Drugs

Kids with ADHD can be restless and difficult to handle. Many of them are treated with drugs, but a new study says food may be the key. Published in The Lancet journal, the study suggests that with a very restrictive diet, kids with ADHD could experience a significant reduction in symptoms.

The study’s lead author, Dr. Lidy Pelsser of the ADHD Research Centre in the Netherlands, writes in The Lancet that the disorder is triggered in many cases by external factors — and those can be treated through changes to one’s environment. “ADHD, it’s just a couple of symptoms — it’s not a disease,” the Dutch researcher tells All Things Considered weekend host Guy Raz.

The way we think about — and treat — these behaviors is wrong, Pelsser says. “There is a paradigm shift needed. If a child is diagnosed ADHD, we should say, ‘OK, we have got those symptoms, now let’s start looking for a cause.’ ”
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According to Pelsser, 64 percent of children diagnosed with ADHD are actually experiencing a hypersensitivity to food. Researchers determined that by starting kids on a very elaborate diet, then restricting it over a few weeks’ time. “It’s only five weeks,” Pelsser says. “If it is the diet, then we start to find out which foods are causing the problems.”

Teachers and doctors who worked with children in the study reported marked changes in behavior. “In fact, they were flabbergasted,” Pelsser says.

Evidence of Extraterrestrial Life Discovered?

Has evidence of extraterrestrial life been discovered? In Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites , Richard B. Hoover, Ph.D. NASA/Marshall Space Flight Center, puts forth his evidence on the discovery of evidence of cyanobacteria in meteorites.

Dr. Hoover has discovered evidence of microfossils similar to Cyanobacteria, in freshly fractured slices of the interior surfaces of the Alais, Ivuna, and Orgueil CI1 carbonaceous meteorites. Based on Field Emission Scanning Electron Microscopy (FESEM) and other measures, Dr. Hoover has concluded they are indigenous to these meteors and are similar to trichomic cyanobacteria and other trichomic prokaryotes such as filamentous sulfur bacteria. He concludes these fossilized bacteria are not Earthly contaminants but are the fossilized remains of living organisms which lived in the parent bodies of these meteors, e.g. comets, moons, and other astral bodies. The implications are that life is everywhere, and that life on Earth may have come from other planets.

The importance of this claim is hard to ignore. The journal includes a statement from Dr. Rudy Schild, Center for Astrophysics, Harvard-Smithsonian, Editor-in-Chief, Journal of Cosmology:

Dr. Richard Hoover is a highly respected scientist and astrobiologist with a prestigious record of accomplishment at NASA. Given the controversial nature of his discovery, we have invited 100 experts and have issued a general invitation to over 5000 scientists from the scientific community to review the paper and to offer their critical analysis. Our intention is to publish the commentaries, both pro and con, alongside Dr. Hoover’s paper. In this way, the paper will have received a thorough vetting, and all points of view can be presented. No other paper in the history of science has undergone such a thorough analysis, and no other scientific journal in the history of science has made such a profoundly important paper available to the scientific community, for comment, before it is published. We believe the best way to advance science, is to promote debate and discussion.

Read the full paper.

The filaments have been observed to be embedded in freshly fractured internal surfaces of the stones. They exhibit features (e.g., the size and size ranges of the internal cells and their location and arrangement within sheaths) that are diagnostic of known genera and species of trichomic cyanobacteria and other trichomic prokaryotes such as the filamentous sulfur bacteria. ESEM and FESEM studies of living and fossil cyanobacteria show similar features in uniseriate and multiseriate, branched or unbranched, isodiametric or tapered, polarized or unpolarized filaments with trichomes encased within thin or thick external sheaths. Filaments found in the CI1 meteorites have also been detected that exhibit structures consistent with the specialized cells and structures used by cyanobacteria for reproduction (baeocytes, akinetes and hormogonia), nitrogen fixation (basal, intercalary or apical heterocysts) and attachment or motility (fimbriae).
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These studies have led to the conclusion that the filaments found in the CI1 carbonaceous meteorites are indigenous fossils rather than modern terrestrial biological contaminants that entered the meteorites after arrival on Earth. The Î´13C and D/H content of amino acids and other organics found in these stones are shown to be consistent with the interpretation that comets represent the parent bodies of the CI1 carbonaceous meteorites. The implications of the detection of fossils of cyanobacteria in the CI1 meteorites to the possibility of life on comets, Europa and Enceladus are discussed.

Has life been found in a meteorite? by Phil Plait
Continue reading →

MIT Engineers Design New Type of Nanoparticle for Vacines

MIT engineers have designed a new type of nanoparticle that could safely and effectively deliver vaccines for diseases such as HIV and malaria. The new particles, described in the Feb. 20 issue of Nature Materials, consist of concentric fatty spheres that can carry synthetic versions of proteins normally produced by viruses. These synthetic particles elicit a strong immune response – comparable to that produced by live virus vaccines – but should be much safer, says Darrell Irvine, author of the paper and an associate professor of materials science and engineering and biological engineering.

Such particles could help scientists develop vaccines against cancer as well as infectious diseases. In collaboration with scientists at the Walter Reed Army Institute of Research, Irvine and his students are now testing the nanoparticles’ ability to deliver an experimental malaria vaccine in mice.

Vaccines protect the body by exposing it to an infectious agent that primes the immune system to respond quickly when it encounters the pathogen again. In many cases, such as with the polio and smallpox vaccines, a dead or disabled form of the virus is used. Other vaccines, such as the diphtheria vaccine, consist of a synthetic version of a protein or other molecule normally made by the pathogen.

When designing a vaccine, scientists try to provoke at least one of the human body’s two major players in the immune response: T cells, which attack body cells that have been infected with a pathogen; or B cells, which secrete antibodies that target viruses or bacteria present in the blood and other body fluids.

For diseases in which the pathogen tends to stay inside cells, such as HIV, a strong response from a type of T cell known as “killer” T cell is required. The best way to provoke these cells into action is to use a killed or disabled virus, but that cannot be done with HIV because it’s difficult to render the virus harmless.

To get around the danger of using live viruses, scientists are working on synthetic vaccines for HIV and other viral infections such as hepatitis B. However, these vaccines, while safer, do not elicit a very strong T cell response. Recently, scientists have tried encasing the vaccines in fatty droplets called liposomes, which could help promote T cell responses by packaging the protein in a virus-like particle. However, these liposomes have poor stability in blood and body fluids.

Irvine, who is a member of MIT’s David H. Koch Institute for Integrative Cancer Research, decided to build on the liposome approach by packaging many of the droplets together in concentric spheres. Once the liposomes are fused together, adjacent liposome walls are chemically “stapled” to each other, making the structure more stable and less likely to break down too quickly following injection. However, once the nanoparticles are absorbed by a cell, they degrade quickly, releasing the vaccine and provoking a T cell response.

read the full press release

Most Genes? A crustacean the size of a grain of rice

photo of Daphnia, a crustacean

“Daphnia are ubiquitous in freshwater ponds and lakes and are often used to assess the health of ponds. Since the creature is so well studied by ecologists, knowing its genetics should reveal a lot about how genes respond to different environments.

The first scientists to describe Daphnia thought they were a kind of flea because they assumed the red color came from sucking blood as fleas do. It turns out they’re not bloodsuckers – they’re blood makers. Daphnia have genes that make hemoglobin, so when the animal is stressed out, those genes switch on and the animal looks red.

In fact Daphnia have an astonishingly large number of genes. “We count more than 31,000 genes,” says [John] Colbourne. By comparison, the human genome has more like 23,000 genes. If Guinness tracks such things, Daphnia would hold the record for the most genes of any animal studied to date.

“Many of those genes – we estimate around 35 percent of them – are brand new to science,”

Daphnia can grow its own spear and helmet when threatened by an attacker

Red-light Cameras Save Lives, Could Save More if Used in More Cities

Red light cameras saved 159 lives in 2004-08 in 14 of the biggest US cities, a new analysis by the Insurance Institute for Highway Safety shows. Had cameras been operating during that period in all large cities, a total of 815 deaths would have been prevented.

“The cities that have the courage to use red light cameras despite the political backlash are saving lives,” says Institute president Adrian Lund. The researchers found that in the 14 cities that had cameras during 2004-08, the combined per capita rate of fatal red light running crashes fell 35 percent, compared with 1992-96. The rate also fell in the 48 cities without camera programs in either period, but only by 14 percent.

The rate of all fatal crashes at intersections with signals — not just red light running crashes — fell 14 percent in the camera cities and crept up 2 percent in the noncamera cities. In the camera cities, there were 17 percent fewer fatal crashes per capita at intersections with signals in 2004-08 than would have been expected. That translates into 159 people who are alive because of the automated enforcement programs.

This result shows that red light cameras reduce not only fatal red light running crashes, but other types of fatal intersection crashes as well. One possible reason for this is that red light running fatalities are undercounted due to a lack of witnesses to explain what happened in a crash. Drivers also may be more cautious in general when they know there are cameras around.

Based on these calculations, if red light cameras had been in place for all 5 years in all 99 US cities with populations over 200,000, a total of 815 deaths could have been avoided.

“Somehow, the people who get tickets because they have broken the law have been cast as the victims,” Lund says. “We rarely hear about the real victims — the people who are killed or injured by these lawbreakers.” Red light running killed 676 people and injured an estimated 113,000 in 2009. Nearly two-thirds of the deaths were people other than the red light running drivers — occupants of other vehicles, passengers in the red light runners’ vehicles, bicyclists, or pedestrians.

Previous research has established that red light cameras deter would-be violators and reduce crashes at intersections with signals. Institute studies of camera programs have found that red light violations fell at intersections where cameras were installed and that this effect also spilled over to intersections without cameras. An Institute study in Oxnard, Calif., found that injury crashes at intersections with traffic signals fell 29 percent citywide after automated enforcement began.

The new study adds to this by showing that cameras reduce not only violations and crashes throughout entire communities but deaths, too.

Red-light cameras save lives, study says

The 2.2 million intersection crashes recorded in 2009 made up about 41 percent of all accidents. They resulted in 81,112 serious injuries and 7,358 deaths. Police established red-light running as the cause of 676 deaths and 113,000 injuries. The vast majority of the people who died – 64 percent – were not driving the vehicle that ran the light. They were passengers, other drivers, pedestrians and cyclists.

Robots That Start as Babies Master Walking Faster Than Those That Start as Adults

In a first-of-its-kind experiment, Bongard created both simulated and actual robots that, like tadpoles becoming frogs, change their body forms while learning how to walk. And, over generations, his simulated robots also evolved, spending less time in “infant” tadpole-like forms and more time in “adult” four-legged forms.

These evolving populations of robots were able to learn to walk more rapidly than ones with fixed body forms. And, in their final form, the changing robots had developed a more robust gait — better able to deal with, say, being knocked with a stick — than the ones that had learned to walk using upright legs from the beginning.

Bongard’s research, supported by the National Science Foundation, is part of a wider venture called evolutionary robotics. “We have an engineering goal,” he says “to produce robots as quickly and consistently as possible.” In this experimental case: upright four-legged robots that can move themselves to a light source without falling over.

Using a sophisticated computer simulation, Bongard unleashed a series of synthetic beasts that move about in a 3-dimensional space. “It looks like a modern video game,” he says. Each creature — or, rather, generations of the creatures — then run a software routine, called a genetic algorithm, that experiments with various motions until it develops a slither, shuffle, or walking gait — based on its body plan — that can get it to the light source without tipping over.

Continue reading →

Video showing malaria breaking into cell

Malaria caught on camera breaking and entering cell [the broken link has been removed]

The Plasmodium parasite responsible for malaria is transmitted by the bite of infected mosquitoes, and is thought to kill almost 1 million people worldwide each year.

Jake Baum at the Walter and Eliza Hall Institute of Medical Research in Melbourne, Australia, and colleagues used transmission electron microscopy and 3D immuno-fluorescence microscopy to record a series of still images during the 30-second-long invasion, and combined them into a movie.

Naturally Curious Children

I write this blog because when I was a kid I was curious and had parents who gave me enough interesting answers and interesting resources to build on that curiosity. And I am still curious today. I love learning. And I love to hear about kids learning.

The Big Girl has worked out evolution

She was ecstatic when we ended up with a rooster in our ‘sexed’ chickens even though Mummy and Daddy weren’t too impressed, because she wants more little fluffy chicks. I think that counts as evidence she knows you need boys and girls to get babies.
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“What would happen if there were no boys?” This is the question she came out with the other day.

“Well, there would be no babies.” I didn’t quite get the problem seeing we were feeding the rather prolific guinea pigs at the time and we’ve been talking about separating them.
“But what if there were no boys at all? So no-one could have babies?”
“Eventually, they would all die.”
“But there wouldn’t be any left!”
“No, they would die out.”
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“How did humans start?”… a puzzled little crease in her forehead. “Because if there weren’t any around with the dinosaurs they must have started sometime. How could there be no humans and then they’re there? What was the Mummy?”
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“Well, they weren’t sudden. You know how you are a little bit different to Mummy and Daddy? That’s how it happened. The babies were just a little bit different to their parents and over a really, really long time they became people.”
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“But if there was only one it would die out.”
Well that came out of nowhere, did I miss half of this conversation?
“You know, the first person. It needs to have both a boy and a girl to have more people babies. So if there was only one it would die out.”
“Oh, from yesterday. Yes, you’re right. But people live in groups, so they’re all changing a tiny little bit at the same time.”

It is great to see developing minds at work. Exploring their natural curiosity. And taking in new information puzzling it out over time and then coming back to the ideas. This kind of curiosity is what drives learning and success.