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VIDEO: Trophic Cascade, How Wolves Change Rivers

3:40 am in Uncategorized by john in sacramento

Just ran across this on Wednesday as I was reading Miss Cellania, and stopped cold when she had the above video posted. Because, WHAT?!? How could wolves change the course of a river. After all, they’re not beavers or anything. They have big fangs, and are the stuff of countless stories around campfires.

But as George Monbiot explains, their behavior, led to a reaction by the deer and elk to avoid areas in which they’d be easily trapped, which led to a regeneration of plants and trees, which led to an explosion in animal wildlife. This is called a Trophic Cascade.

That video is a shortened version of this TED talk where Monbiot later mentions whales, and how the Japanese argued that killing whales would increase the numbers of fish and krill —- it actually has had the opposite effect. And he also explains how when whales were at their historical high numbers (before whaling) they were indirectly responsible for disposing of tens of millions of tons of carbon absorbed from the atmosphere every year.

Another example is sea otters and seals. Sea otters and seals have been killed for their fur because the fashionistas demanded it. A reduction in sea otters and seals led to an explosion in the population of sea urchins, which the otters eat. So, the runaway population of sea urchins ravaged the kelp forests. And, a wildlife ecologist explained on a reddit thread better than I ever could

… so the kelp forests were reduced, decreasing habitat for a multitude of fishes, which decreased seal numbers, which forced orcas to switch from eating seals to eating more fish (and reducing their numbers even more). Reintroductions of sea otters has reversed this cascade in many areas. Ecology is so cool.

You wouldn’t think one bad decision would adversely effect things so much. But the Butterfly Effect of Trophic Cascading really does make a huge difference

Happy π Day (3.14), and 7 more cool numbers

8:06 pm in Uncategorized by john in sacramento

Dunno how accurate this is because I’m not a musician, but pretty cool

The discovery and refinement of pi was a result of a collaboration over centuries from the Babylonians, to Archimedes, to Tsu Chung-Chi, to Leonardo … on through today

Why do you need pi? You can use pi to find the area of a circle … π r ² … 3.14 times the radius squared.

7 Numbers That Are Just as Cool as Pi. From the number one, to Euler’s Number, to Tau, and Phi (the golden ratio)

Anti-gravity-like Magic … Srsly | Neil deGrasse Tyson: “We’ve Stopped Dreaming” | NASA Derived R&D Technology

7:39 pm in Uncategorized by john in sacramento

Just to be clear, it’s not anti-gravitational, it just seems that way. And it’s not magic, it just seems that way, it’s the world we live in

Why does the magnet fall so slowly? It’s a combination of Faraday’s and Lenz’s Laws. The falling magnet isn’t attracted to copper (non ferrous metal), but the movement through, or over, or near the copper (aluminum works also) induces a current which causes a change in the magnetic flux that reacts with the magnetic field of the the magnet itself. More


The magnet induces currents in the copper pipe as it falls because, at any point in the pipe, there is a change in magnetic flux. By Faraday’s Law this induces and emf, and hence a current that, by Lenz’s Law, opposes the motion. So as the magnet falls vertically, the change in flux below the falling magnet produces a repulsive force, i.e., an upward force (opposite to gravity), and the change in flux above the falling magnet produces an attractive force, i.e., an upward force also (opposite to gravity). The magnitude of these upward forces depends on the speed of the magnet, the faster the magnet falls the greater the upward force. When the upward force equals the weight of the magnet, the latter will reach its terminal velocity (since there will be no net force acting on it). With a plastic pipe, an emf is generated, but since plastic is an insulator, there will be no currents and so there will be no upward forces.


Must Listen: Neil deGrasse Tyson’s inspirational rant on NASA cutbacks

First of all, let’s clarify what the NASA budget is. Do you realize that the $850 billion dollar bailout, that sum of money is greater than the entire 50-year running budget of NASA?And so when someone says, “We don’t have enough money for this space probe,” I’m asking, no, it’s not that you don’t have enough money, it’s that the distribution of money that you’re spending is warped in some way that you are removing the only thing that gives people something to dream about tomorrow.

You remember the 60s and 70s. You didn’t have to go more than a week before there’s an article in Life magazine, “The Home of Tomorrow,” “The City of Tomorrow,” “Transportation of Tomorrow”. All of that ended in the 1970s. After we stopped going to the Moon, it all ended. We stopped dreaming.

And so I worry that the decision that Congress makes doesn’t factor in the consequences of those decisions on tomorrow. Tomorrow’s gone. They’re playing for the quarterly report, they’re playing for the next election cycle, and that is mortgaging the actual future of this nation, and the rest of the world is going to pass us by.

50 Consumer Technologies Developed by NASA in the Last 50 Years

Every year NASA publishes a new edition of their Spinoff magazine, a periodical that outlines NASA-based technologies that have disseminated into everyday devices, improving our lives beyond giving us some nifty new desktop wallpapers. This year marks the 50th anniversary of Spinoff, and to celebrate, NASA has created a “best of” list (that we pasted after the jump). From the aerodynamic principles applied to tractor trailers to advanced imaging techniques that allow 360-degree Real Estate photo tours, NASA demonstrates that their technological breakthroughs are about more than just sticking an American flag on the moon.


    Health and MedicineRobotics Offer Newfound Surgical Capabilities 

    In-Line Filtration Improves Hygiene and Reduces Expense

    LED Device Illuminates New Path to Healing

    Polymer Coats Leads on Implantable Medical Device

    Lockable Knee Brace Speeds Rehabilitation

    Robotic Joints Support Horses and Humans

    Photorefraction Screens Millions for Vision Disorders

    Periodontal Probe Improves Exams, Alleviates Pain

    Magnetic Separator Enhances Treatment Possibilities


    Lithium Battery Power Delivers Electric Vehicles to Market

    Advanced Control System Increases Helicopter Safety

    Aerodynamics Research Revolutionizes Truck Design