Author Archives: curiouscat

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.
…
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.

Pepsi Bottles Made of Switch Grass and Other Plants

Pepsi bottles: no more plastic

The bottle is made from switch grass, pine bark, corn husks and other materials. Ultimately, Pepsi plans to also use orange peels, oat hulls, potato scraps and other leftovers from its food business. The new bottle looks, feels and protects the drink inside exactly the same as its current bottles, said Rocco Papalia, senior vice president of advanced research at PepsiCo.
…
PepsiCo says it is the world’s first bottle of a common type of plastic called PET made entirely of plant materials. Coca-Cola Co. currently produces a bottle using 30 percent plant-based materials and recently estimated it would be several years before it has a 100 percent plant bottle that’s commercially viable.
…
“This is the beginning of the end of petroleum-based plastics,” said Allen Hershkowitz, a senior scientist with the Natural Resources Defense Council and director of its waste management project. “When you have a company of this size making a commitment to a plant-based plastic, the market is going to respond.”

Coca-Cola said it welcomed other advances in packaging, but noted that it has scaled up use of its own plant-based bottle since introducing it in 2009. It also says it has demonstrated a 100 percent plant bottle in the lab and is still working to ensure it is commercially viable.

There are other plant-based plastics available or in development, but Herskowitz said these are not environmentally preferred because they typically use plants grown solely for that purpose rather than using the estimated 2 billion tons of agricultural waste produced each year. And these alternative plastics cannot be recycled.

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.’ ”
…
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.

Finding Huge Sources of Energy Without Increasing Carbon Dioxide Output

Bill Gates talking about energy, and climate change, at TED. He is looking at a new type of nuclear reactor using as fuel, what is now nuclear waste.

The idea of Terrapower is that, instead of burning a part of uranium, the one percent, which is the U235, we decided, let’s burn the 99 percent, the U238. It is kind of a crazy idea. In fact, people had talked about it for a long time, but they could never simulate properly whether it would work or not, and so it’s through the advent of modern supercomputers that now you can simulate and see that, yes, with the right material’s approach, this looks like it would work.

And, because you’re burning that 99 percent, you have greatly improved cost profile. You actually burn up the waste, and you can actually use as fuel all the leftover waste from today’s reactors. So, instead of worrying about them, you just take that. It’s a great thing. It breathes this uranium as it goes along. So it’s kind of like a candle. You can see it’s a log there, often referred to as a traveling wave reactor. In terms of fuel, this really solves the problem. I’ve got a picture here of a place in Kentucky. This is the left over, the 99 percent, where they’ve taken out the part they burn now, so it’s called depleted uranium. That would power the U.S. for hundreds of years. And, simply by filtering sea water in an inexpensive process, you’d have enough fuel for the entire lifetime of the rest of the planet.

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).
…
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 →

Lobopodians from China a Few Million Years Ago

image of a lobopodian fosil nicknamed the walking cactus

image of a lobopodian fosil from Nature

Cactus Walking On 20 Legs Found In China

There was a wild period — roughly 520 million years ago — when life, for no obvious reason, burst into a crazy display of weird new fantastic forms — producing creatures in shapes never seen before or since. Consider this animal, the newest fossil discovery from Jianni Liu in China. She calls it “the walking cactus.”

This is not a plant, not a sculpture. It was a live animal, with no eyes, what may or may not be a head, mostly a gaggle of limbs, armor-plated, covered in thorns, attached to a stomach.

What is it? Taxonomically, Jianni Liu thinks it’s a lobopodian, a group of animals described as “worms with legs.” Lobopodians are about the craziest looking critters that ever lived. A whole zoo of them appear in the rocks around Chengjiang, China.
…
All we know, says Richard Fortey in his classic history Life, is that a long time ago, the first of these strange animals popped into view and for a short while “there was a chain reaction, unstoppable once it started, a bacchanalia of zoological inventiveness, which has never been matched again.”

Every living thing on earth today is what’s left over from that amazing burst of forms. It’s true we now live on land and in the air, not just in the sea. We have grasses and flowers and beetles in more varieties than you can imagine, and yet, in some deep architectural way, the developmental paths were set way back then, 500 million years ago. The Walking Cactus is just another souvenir of that crazy moment.

Very cool. Actual science is so full of such interesting things. The Cambrian explosion of life, about 540-490 million years ago, marked the beginning of complex life on earth. Before Cambrian, the sea floor was covered by microbial mats. By the end of the period, burrowing animals had destroyed the mats through bioturbation, and gradually turned the seabeds into what they are today. Generally it is accepted that there were no land plants at this time, although it is likely that a microbial “scum” comprising fungi, algae, and possibly lichens covered the land.

Complex organisms gradually became more common in the millions of years immediately preceding the Cambrian, but it was not until this period that mineralized (readily fossilized) organisms became common. Before about 580 million years ago, most organisms were simple, composed of individual cells occasionally organized into colonies. Over the following 70 or 80 million years the rate of evolution accelerated by an order of magnitude (as defined in terms of the extinction and origination rate of species) and the diversity of life began to resemble today’s.

Cats Connect with People, and Particularly Women, as Social Partners

Cats Adore, Manipulate Women

The study is the first to show in detail that the dynamics underlying cat-human relationships are nearly identical to human-only bonds, with cats sometimes even becoming a furry “child” in nurturing homes.

“Food is often used as a token of affection, and the ways that cats and humans relate to food are similar in nature to the interactions seen between the human caregiver and the pre-verbal infant,” co-author Jon Day, a Waltham Centre for Pet Nutrition researcher, told Discovery News. “Both cat and human infant are, at least in part, in control of when and what they are fed!”
…
The researchers determined that cats and their owners strongly influenced each other, such that they were each often controlling the other’s behaviors. Extroverted women with young, active cats enjoyed the greatest synchronicity, with cats in these relationships only having to use subtle cues, such as a single upright tail move, to signal desire for friendly contact.

While cats have plenty of male admirers, and vice versa, this study and others reveal that women tend to interact with their cats — be they male or female felines — more than men do.
…
Cats also seem to remember kindness and return the favors later. If owners comply with their feline’s wishes to interact, then the cat will often comply with the owner’s wishes at other times. The cat may also “have an edge in this negotiation,” since owners are usually already motivated to establish social contact.
…
co-author Dorothy Gracey of the University of Vienna explained. “A human and a cat can mutually develop complex ritualized interactions that show substantial mutual understanding of each other’s inclinations and preferences.”

Readers of this blog already know how great cats are, but this is more evidence on how wonderful they are.

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

Great 3D Printing Presentation

Very fun presentation by 10 year old on 3D printing and the open source Makerbot at Ignite Phoenix.

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