gif(1) and (2) and the last one represents elastic collisions in one dimension. The kinetic energy and the momentum just before and after the collision is conserved. Mathematically this means that ;
- m1*v1+ m2*v2 = m1*v1’ + m2*v2’. where v’ means the velocity right after the collision.
- ½*m1*(v1)² + ½*m2*(v2)² = 1/2*m1*(v1’)² + ½*m2*(v2’)²
combining these two gives you this equation ;
v1 - v2 = v2’ - v1’
go on and demonstrate it!
The third gif represents a perfect inelastic collision. In this case you have that m1*v1+ m2*v2 = m1*v1’ + m2*v2’ but since its perfectly inelastic the final velocities are the same since both objects are sticked together. The total kinetic energy is not conserved tho.
Polar bears range from Russia to the U.S. (Alaska), from Canada to Greenland, and onto Norway’s Svalbard archipelago—the five polar bear nations.
Biologists estimate there are 20,000 to 25,000 bears. About 60% of those live in Canada.
At the 2009 meeting of the IUCN Polar Bear Specialist Group, scientists reported that of the19 populations of polar bears:
- 8 are declining
- 3 are stable
- 1 is increasing
- 7 have insufficient data
By comparison, in 2005:
- 5 were declining
- 5 were stable
- 2 were increasing
- 7 have insufficient data
In May 2008, the U.S listed the polar bear as a threatened species under the Endangered Species Act. In Canada, polar bears are listed as a species of special concern. Russia also considers the polar bear a species of concern.
What’s happening? Today, scientists have concluded that the threat to polar bears is loss of their sea ice habitat in the Arctic from global warming. Polar bears depend on sea ice for hunting, breeding, and in some cases, denning. Summer ice loss in the Arctic now equals an area the size of Alaska, Texas, and the state of Washington combined.
Photos by: Nikolai Zinoviev (1, 5) | Marco Gaiotti (2, 6) | Dmytro Cherkasov (3) | Andy Rouse (4)
Polar Bears International | Donate | Adopt | Sea Ice Loss Video
“The sky calls to us. If we do not destroy ourselves, we will one day venture to the stars.”
I made these to fit the Facebook cover photo size - feel free to use them with the post’s link. Photo courtesy: ESA/NASA.
Tree Mountain - 11,000 Trees planted by 11,000 People, protected for 400 years.
In 1996 Finland,Ylöjärvi the Tree Mountain project led by Agnes Denes was completed. A huge ecological and artistic work based around the plantation of 11,000 trees in a complex geometric pattern (see third photo) by 11,000 people. Upon completion Martti Ahtisaari the then president of Finland declared the area protected land to be maintained for four centuries, eventually creating a virgin forest. The trees were planted in an mathematical pattern derived from a combination of the golden ratio and the fibonacci numbers. The mountain has since then been allowed to grow evolving and growing from the original pattern (see last four images).
“The forest will be kept for the next 400 years, thereby creating the first manmade virgin forest. It will take that long for the environment to re-create itself. The 11,000 people who came to plant the trees received a certificate valid for four centuries that they can leave to their children as custodians of the trees. My forests are mathematical in order to combine the human intellect with the majesty of nature. I restore the land, rejuvenate it, and fill it with wonders of new human understanding.” Agnes Denes
Agnes Denes is certainly a visionary managing to incorporate science, mathematics and philosophy into her work. The site itself was created from refuse material from a gravel pit further enhancing the sustainable ethos.
It would great to visit the site on the 20th anniversary in 2016 to carry out ecological analysis of the entire site. Answering questions regarding the biodiversity of the forest, the amount of carbon captured/stored, the air quality and perhaps also contributions to the water quality of the forest.This forest continues to grow and will hopefully be protected till 2396. Read more American Scientist Regeneration on Tree Mountain.
Research from Oregon Health & Science University’s Vollum Institute, published in the current issue of Nature (1, 2), is giving scientists a never-before-seen view of how nerve cells communicate with each other. That new view can give scientists a better understanding of how antidepressants work in the human brain — and could lead to the development of better antidepressants with few or no side effects.
The article in today’s edition of Nature came from the lab of Eric Gouaux, Ph.D., a senior scientist at OHSU’s Vollum Institute and a Howard Hughes Medical Institute Investigator. The article describes research that gives a better view of the structural biology of a protein that controls communication between nerve cells. The view is obtained through special structural and biochemical methods Gouaux uses to investigate these neural proteins.
The Nature article focuses on the structure of the dopamine transporter, which helps regulate dopamine levels in the brain. Dopamine is an essential neurotransmitter for the human body’s central nervous system; abnormal levels of dopamine are present in a range of neurological disorders, including Parkinson’s disease, drug addiction, depression and schizophrenia. Along with dopamine, the neurotransmitters noradrenaline and serotonin are transported by related transporters, which can be studied with greater accuracy based on the dopamine transporter structure.
The Gouaux lab’s more detailed view of the dopamine transporter structure better reveals how antidepressants act on the transporters and thus do their work.
The more detailed view could help scientists and pharmaceutical companies develop drugs that do a much better job of targeting what they’re trying to target — and not create side effects caused by a broader blast at the brain proteins.
“By learning as much as possible about the structure of the transporter and its complexes with antidepressants, we have laid the foundation for the design of new molecules with better therapeutic profiles and, hopefully, with fewer deleterious side effects,” said Gouaux.
Gouaux’s latest dopamine transporter research is also important because it was done using the molecule from fruit flies, a dopamine transporter that is much more similar to those in humans than the bacteria models that previous studies had used.
The dopamine transporter article was one of two articles Gouaux had published in today’s edition of Nature. The other article also dealt with a modified amino acid transporter that mimics the mammalian neurotransmitter transporter proteins targeted by antidepressants. It gives new insights into the pharmacology of four different classes of widely used antidepressants that act on certain transporter proteins, including transporters for dopamine, serotonin and noradrenaline. The second paper in part was validated by findings of the first paper — in how an antidepressant bound itself to a specific transporter.
“What we ended up finding with this research was complementary and mutually reinforcing with the other work — so that was really important,” Gouaux said. “And it told us a great deal about how these transporters work and how they interact with the antidepressant molecules.”
(Source: ohsu.edu)
Pistol Shrimp and Goby Symbiosis
Some species of pistol shrimps and of Goby fishes share a close symbiotic relationship, living together in the same burrow
The shrimp builds and maintains the burrow, which is inhabited by both the fish and the shrimp. In return for the home, the goby keeps watch for predators, and alerts the shrimp to retreat inside the burrow through several tail flicks should danger be present. This benefits the shrimp as it has poor eyesight.
When searching for food away from the burrow, the shrimp maintains contact with the goby using its antennae. The goby guides the shrimp and warns it should any predators approach.
This type of symbiotic relationship, where both participants gain benefit, is known as mutualism.
Klaus Stiefel on Flickr
we live in a world where the pizza arrives faster than the police
Well the pizza driver faces consequences when their job isn’t done right.
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YTMND’s presentation of our future in all its horrifying glory.
How The Face Changes With Shifting A Light Source
Pregnant Australian Ghost Bat having an ultrasound at Featherdale Wildlife Park, Sydney, Australia
Hi somersaulters
Here is an Amino Acids Reference Chart for you.
Hope you like it :)
http://ift.tt/1dBODrJ http://ift.tt/1bWQO2h
Hummingbird Clearwing Moth (Hemaris thysbe) visiting the flowers of Butterfly Bush (Buddleia davidii)), Pennsylvania, USA.
(photo: Victoria Bush)
Salvador Dali – Ménagère (Cutlery Set) 1957
Six pieces (silver-gilt) comprising of two forks, two knives and two enameled spoons.
Portable Hydrogen Reactors - The Future Is Here
You’re on the go and your phone just ran out of juice, maybe you have a portable charger handy but it’s not likely that you will get more than one charge out of it. But what if you had a portable power generator which could provide enough power to run your phone for a week? This is where the Brunston Hydrogen Reactor steps in; you may recognise that it bears some similarities to the Horizon Fuel-Cell MiniPak, which just so happens to be the device it was modelled on. The main changes seen between the two are the aesthetics, an increase in sturdiness in the Brunston as it is marketed towards hikers and campers, and higher capacity fuel cells.
So how does it work?
The 3-inch fuel cells are full of hydrogen which is stored as a hydride and this hydrogen is split apart using a platinum catalyst as to separate the positively charged H+ ions and the negative electrons and use them to create a electrical potential gradient, or, voltage. The device then routes the electrons through some wires and a USB port to charge your device, while the H+ ions are expelled through an electrolyte membrane where they combine with oxygen to form water vapour.As the hydrogen is stored in a hydride its stability is increased and the device has been cleared for carry-on luggage in airplanes - however you cannot carry more than two hydrogen cells with you. The cells feature a 8,500 mAh capacity at an output of 5V with a choice of either 1A or 2A which you can select using a toggle switch. Once a fuel cell is depleted they can be charged again in about an hour, but sadly this ability will have to wait until you get home as the device used to charge them isn’t portable and requires a wall socket. Brunton is working to find a way to provide free in-store charging stations as the at home hydrolyser charging device costs $250.
I for one am very excited to see this awesome tech hit the market and may make use of it for my long trips into the mountains with my camera in the future! What would you use this tech for a what improvements would you like to see in the future?