Author Archives: curiouscat

Thorium Nuclear Reactors

Kirk Sorensen is founder of Flibe Energy and is an advocate for nuclear energy based on thorium and liquid-fluoride fuels and author of Energy From Thorium blog.

He also taught nuclear engineering at Tennessee Technological University as a guest lecturer. He is active in nonprofit advocacy organizations such as the Thorium Energy Alliance and the International Thorium Energy Organization. He is married and has four small children.

See another video with him on why the thorium molten-salt reactor wasn’t developed (from a Google tech talk).

Science Continues to Explore Causes of Weight Gain

Science is amazing when it explains very cool ideas. It is also very interesting (if a bit frustrating) when the scientific inquiry process is ongoing and open to debate. Weight gain is one such area that is of great concern and large amount of study but some issues are still unclear. I have discussed this before. I think that calories in compared to calories consumed is a good first approximation. I believe it makes sense that the efficiency of our bodies at capturing the calories and turning them into weight gain could be affected by things other than the total calories in. It might be the type of calories or it might be other factors (bacteria or chemical present)…

What’s Really Making Us Fat?

Researchers in a relatively new field are looking at the role of industrial chemicals and non-caloric aspects of foods — called obesogens — in weight gain. Scientists conducting this research believe that these substances that are now prevalent in our food supply may be altering the way our bodies store fat and regulate our metabolism. But not everyone agrees. Many scientists, nutritionists, and doctors are still firm believers in the energy balance model. A debate has ensued, leaving a rather unclear picture as to what’s really at work behind our nation’s spike in obesity.
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A widely reported study that came out in January in The American Journal of Clinical Nutrition (AJCN) would seem to dispute this finding: it confirms the belief in the energy balance model, and has been cited as proof by many researchers working in the field. I asked an author of the study, Dr. George Bray, professor of medicine at Louisiana State University, about the myriad of additives and industrial ingredients in our food that were not accounted for in this study. “It doesn’t make any difference,” he said in a telephone interview. “Calories count. If you can show me that it doesn’t work, I’d love to see it. Or anybody else who says it doesn’t — there ain’t no data the other way around.”

It seems to me that it certainly makes sense to reduce calories if you need to lose weight. And it sure seems the strongest evidence is for calories being the most important factor.

I also believe exercise is good, for overall health. It also seems more and more evidence is being found about how difficult it is to lose weight which reinforces the importance of preventing the weight gain in the first place.

Dolphins Saved by People

Is this a bit like man bites dog? In any case it is a happy event. I wish I could have helped.

Star Stuff: The Universe is In Us

Great statement from Neil DeGrasse Tyson on “what is the most astounding fact you can share with us about the universe.”

“The atoms that comprise life on earth, the atoms that make up the human body, are traceable to the crucibles that cooked light elements into heavy elements in their core under extreme temperatures and pressures. These stars, the high mass ones among them, went unstable in their later years. They collapsed and then exploded scattering their enriched guts across the galaxy. Guts made of carbon, nitrogen, oxygen, and all the fundamental ingredients of life itself. These ingredients become part of gas clouds that condense, collapse, form the next generation of solar systems: stars with orbiting planets. And those planets now have the ingredients for life itself. So when I look up at the night sky and I know that, yes we are part of this universe, we are in this universe, but perhaps more important than both of those facts, is that the universe is in us… my atoms came from those stars….”

I think this might well be my thought on the most astounding fact also. Ever since I learned the atoms we are made of were created inside stars it has never ceased to amaze me.

Neil DeGrasse Tyson is amazing. I would edit his statement a bit myself, though, to make it:

“The most astounding fact is that the atoms that comprise life on earth, the atoms that make up the human body, were created in the crucible of stars that cooked light elements into heavy elements. Those stars went unstable, in their later years: they collapsed and then explored scattering their enriched cores across the galaxy. Those stars made the carbon, nitrogen, oxygen, and all the fundamental ingredients of life itself. Those ingredients became part of gas clouds that condensed to form the next generation of solar systems: stars with orbiting planets. And those planets have the ingredients for life. So when I look up at the night sky, I know that my atoms came from the predecessors of the stars I see.”

The Information: A History, a Theory, a Flood by James Gleick

James Gleick is a great science writer. I remember first reading his book, Chaos, which I loved. He continues to write engaging and entertaining books on science. His 2011 release The Information: A History, a Theory, a Flood, is now available in paperback.

From the invention of scripts and alphabets to the long-misunderstood talking drums of Africa, Gleick tells the story of information technologies that changed the very nature of human consciousness. Gleick provides portraits of the key figures contributing to the inexorable development of our modern understanding of information: Charles Babbage, the idiosyncratic inventor of the first great mechanical computer; Ada Byron, the brilliant and doomed daughter of the poet, who became the first true programmer; pivotal figures like Samuel Morse and Alan Turing; and Claude Shannon, the creator of information theory itself.

And now the information age arrives. The Information is the story of how we got here and where we are heading.

Breakfast with Cheetahs, Lions and Gazelles

Breakfast with cheetahs

For ten days I’ll be touring wildlife camps in Namibia and Botswana, accompanying researchers as they gather data on big cats, black rhinos, and elephants. Ecotourism – trips where travelers help preserve the communities they visit – is the fastest-growing segment of the tourism industry. A growing number of small U.S. travel firms have found their niche creating trips that combine some element of giving back with comfortable accommodations that don’t stress the environment.

One company is Classic Africa, which arranges small group trips to wildlife camps in Botswana, Namibia, South Africa, Zambia, and Zimbabwe. The firm was founded by Margaret and Pierre Faber, who provide custom trips for about 500 clients a year

I have twice gone on safaris in East Africa (photos from my Kenya safari). They have been absolutely wonderful experiences getting to see vast expanses of natural wildlife is like nothing else I have done. They are costly but if you can afford it they really are quite amazing. While the TV shows exploring these location don’t equal a visit they are pretty great also.

Exploring Eukaryotic Cells

This webcast is packed with information on the makeup and function of eukaryotic cells, which are the type of cells found in animals. It is part of a interesting series of science webcasts by Crash Course. The webcast style might be a bit too hyperactive and flippant for some but the content is quite interesting and the videos they are are of similar style and quality so if you like this one you can subscribe to their channel. They offer quite a few webcasts on science but they also offer webcasts on history.

Bacteriophages Enter Bacteria Using an Iron Tipped Spike

Bacteria-Killing Viruses Wield an Iron Spike

Forget needles in haystacks. Try finding the tip of a needle in a virus. Scientists have long known that a group of viruses called bacteriophages have a knack for infiltrating bacteria and that some begin their attack with a protein spike. But the tip of this spike is so small that no one knew what it was made of or exactly how it worked. Now a team of researchers has found a single iron atom at the head of the spike, a discovery that suggests phages enter bacteria in a different way than surmised.

Wherever there are bacteria you will find bacteriophages; digestive tracts, contaminated water, and feces are usually a good start. These viruses begin their dirty work by drilling into the outer membrane of bacteria. Once completely through all of a bug’s defenses, the phages inject their DNA, which essentially turns the bacterium into phage-producing factories. Eventually, the microbes become filled with so many viruses that they burst, releasing a new horde of phages into the environment.

Bacteriophages are amazing. It is so interesting to learn about amazingly creative solutions that have evolved over time. Real-life science is not easy to match with fiction that springs from our imaginations.

How Bee Hives Make Decisions

The Secret Life of Bees by Carl Zimmer

The decision-making power of honeybees is a prime example of what scientists call swarm intelligence. Clouds of locusts, schools of fish, flocks of birds and colonies of termites display it as well. And in the field of swarm intelligence, Seeley is a towering figure. For 40 years he has come up with experiments that have allowed him to decipher the rules honeybees use for their collective decision-making. “No one has reached the level of experimentation and ingenuity of Tom Seeley,” says Edward O. Wilson of Harvard University.
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Enthusiasm translates into attention. An enthusiastic scout will inspire more bees to go check out her site. And when the second-wave scouts return, they persuade more scouts to investigate the better site.

The second principle is flexibility. Once a scout finds a site, she travels back and forth from site to hive. Each time she returns, she dances to win over other scouts. But the number of dance repetitions declines, until she stops dancing altogether. Seeley and his colleagues found that honeybees that visit good sites keep dancing for more trips than honeybees from mediocre ones.

This decaying dance allows a swarm to avoid getting stuck in a bad decision. Even when a mediocre site has attracted a lot of scouts, a single scout returning from a better one can cause the hive to change its collective mind.
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“Bees are to hives as neurons are to brains,” says Jeffrey Schall, a neuroscientist at Vanderbilt University. Neurons use some of the same tricks honeybees use to come to decisions. A single visual neuron is like a single scout. It reports about a tiny patch of what we see, just as a scout dances for a single site. Different neurons may give us conflicting ideas about what we’re actually seeing, but we have to quickly choose between the alternatives. That red blob seen from the corner of your eye may be a stop sign, or it may be a car barreling down the street.

To make the right choice, our neurons hold a competition, and different coalitions recruit more neurons to their interpretation of reality, much as scouts recruit more bees

Very cool stuff.

Milky Way May Have 100,000 Times More Nomad Planets Than Stars

There may be 100,000 times more “nomad planets” in the Milky Way than stars, according to a new study by researchers at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), a joint institute of Stanford University and the SLAC National Accelerator Laboratory. How amazing is that. Science is so cool. I had no idea this was the case.

If observations confirm the estimate, this new class of celestial objects will affect current theories of planet formation and could change our understanding of the origin and abundance of life.

“If any of these nomad planets are big enough to have a thick atmosphere, they could have trapped enough heat for bacterial life to exist,” said Louis Strigari, leader of the team that reported the result in a paper: Nomads of the Galaxy. Although nomad planets don’t bask in the warmth of a star, they may generate heat through internal radioactive decay and tectonic activity.

Searches over the past two decades have identified more than 500 planets outside our solar system, almost all of which orbit stars. Last year, researchers detected about a dozen nomad planets, using a technique called gravitational microlensing, which looks for stars whose light is momentarily refocused by the gravity of passing planets.

The research produced evidence that roughly two nomads exist for every typical, so-called main-sequence star in our galaxy. The new study estimates that nomads may be up to 50,000 times more common than that.

To arrive at what Strigari himself called “an astronomical number,” the KIPAC team took into account the known gravitational pull of the Milky Way galaxy, the amount of matter available to make such objects and how that matter might divvy itself up into objects ranging from the size of Pluto to larger than Jupiter. Not an easy task, considering no one is quite sure how these bodies form. According to Strigari, some were probably ejected from solar systems, but research indicates that not all of them could have formed in that fashion.

“To paraphrase Dorothy from The Wizard of Oz, if correct, this extrapolation implies that we are not in Kansas anymore, and in fact we never were in Kansas,” said Alan Boss of the Carnegie Institution for Science, author of The Crowded Universe: The Search for Living Planets, who was not involved in the research. “The universe is riddled with unseen planetary-mass objects that we are just now able to detect.”

A good count, especially of the smaller objects, will have to wait for the next generation of big survey telescopes, especially the space-based Wide-Field Infrared Survey Telescope and the ground-based Large Synoptic Survey Telescope, both set to begin operation in the early 2020s.

A confirmation of the estimate could lend credence to another possibility mentioned in the paper – that as nomad planets roam their starry pastures, collisions could scatter their microbial flocks to seed life elsewhere.

Additional authors included KIPAC member Matteo BarnabÃ¨ and affiliate KIPAC member Philip Marshall of Oxford University. The research was supported by NASA, the National Science Foundation and the Royal Astronomical Society.