The painful and debilitating effects of osteoarthritis at the knee can be remedied by replacing the damaged articulating surfaces of the kne...
The painful and debilitating effects of osteoarthritis at the knee can be remedied by replacing the damaged articulating surfaces of the knee with a total knee replacement. Modern knee replacements consist of a metal alloy component on the femoral side (top of the knee) and a special plastic called ultra-high molecular weight polyethylene on the tibial side (bottom of the knee). Through recent improvements in materials, these implants have seen increased longevity, often lasting 15 years or more in the body before requiring a second surgery. As patients opt for knee replacements earlier in life, remain more active after surgery and live longer, the demands on the design and longevity of knee replacements increases.nnOne of the leading causes of revision surgery is periprosthetic bone loss, which means that bone near the implant has thinned. As the knee articulates during walking, the top metal component slides, rolls and rotates on the polyethylene. This relative motion causes the polyethylene to wear. Microscopic debris leaves the surface and enters the surrounding tissue, where it can set off a cascade of cellular reactions that lead to bone resorption. Currently, knee replacement designs and materials are evaluated before being implanted by machines that run accelerated tests by simulating the motion of walking at the knee.nnHowever, walking is not the only activity of daily living. Sitting in a chair, rising from a chair, stepping up a stair and stepping down a stair are the most common activities for total knee replacement patients after walking. In a motion analysis lab, we measured the movements and dynamics of these activities using retroreflective markers, infrared cameras and force plates. Using a computational method known as inverse dynamics and a parametric numerical model, we were able to show that these activities generally have larger motions and higher forces. In particular, the secondary motions of the knee, such as internal-external rotation and medial-lateral (side-to-side) translation, are often larger in non-walking activities.nnUltra-high molecular weight polyethylene, the plastic most commonly used in knee replacements, is made of long chains of molecules. The material is highly wear resistant because the chains are entangled. As thousands of cycles of walking accumulate, the molecular chains align in the primary direction of motion. Once aligned, the material is more susceptible to wear in secondary directions. The larger secondary motions of other activities could lead higher wear. Because pre-implantation tests only include walking, the tests may be insufficient to accurately predict the wear of the implant in the body.nnCurrently, testing is underway to evaluate if the motions of non-walking activities do increase the wear of knee replacements. In addition, knee replacements that had been implanted and were retrieved from patients after revision surgery or death are being evaluated for wear. The results of these retrieved specimen will help determine whether the inclusion of non-walking activities in testing routines is necessary to evaluate the wear of total knee replacements.nnMy dance to explain my in-progress PhD thesis was originally choreographed for live performance and adapted for the camera. Less
The sun creates a lot of energy by hydrogen fusion. Scientists are investigating fusion, building our own ‘sun on earth’, as a sustainab...
The sun creates a lot of energy by hydrogen fusion. Scientists are investigating fusion, building our own ‘sun on earth’, as a sustainable energy source on earth. A lot of energy is released when hydrogen isotopes fuse together into helium and neutrons. One of the key problems is that these high energy neutrons can damage the crystal structure of the surrounding tungsten wall. This can create vacancies in the metal lattice, which trap hydrogen atoms. Trapped hydrogen cannot fuse to release energy.nnMaterial temperature turns out to be an important factor in managing hydrogen capture. We investigated how hydrogen can escape if the tungsten material is hot. On the one hand, hot tungsten atoms are more mobile and can move back into vacancies in the crystal, so that the metal effectively heals itself. Additionally, the hydrogen atoms themselves have a higher mobility at a high temperature. They can now escape from their captivity and take part in the fusion process within the heart of the machine; one step closer to creating a sun on earth.nnMy PhD dance is performed around and on the experiment I’m using for my research, Magnum-PSI (FOM Institute DIFFER, the Netherlands). Magnum-PSI is capable of reproducing the conditions that we expect in the wall of a fusion reactor. We can therefore test materials on their capabilities of withstanding such a harsh environment.nnI would like to thank all people that helped me create this dance. We had an incredible amount of fun using the experimental hall in the weekend for a completely different purpose than the usual experiments. Special thanks to FOM Institute DIFFER (www.differ.nl).nnExplanation of my PhD dance in detail:nThe two dancers at the platform on top of the machine illustrate the fusion of two hydrogen atoms (yellow dresses) into helium within the sun. An abundance of energy is released in this way. Looking down from the machine, we see a single hydrogen atom ‘on earth’. Her movements are the same as in the duet, however much smaller. She dances alone to show that when too much hydrogen is captured in the surrounding wall of a fusion reactor, there is not enough hydrogen to keep the fusion process going.nIn the following scene, we see the regular structure of a tungsten material, depicted by the disks on the ground and the three dancers (black dresses). Smoke rings illustrate the high energy neutrons that, released in the fusion reaction, continuously bombard the material. An interaction between neutrons and the tungsten materials will not happen often, but when it does it will cause a chain reaction of displacements in the material; the frisbees move in all directions. nAt low surface temperature (blue light), the hydrogen atoms are more easily trapped and hence can no longer take part in a fusion reaction. The yellow dancers are captured in the material, they join in on the movements of the black dancers.n At high surface temperatures (red light) the hydrogen atoms have a higher mobility, which prevents them from getting trapped within the material. Their movements are wider and more energetic. Additionally, the material itself regenerates. The disks return to a regular structure, limiting the number of vacancies in which hydrogen can be captured. Now liberated, the yellow hydrogen atoms escape and dance away from the material. n The dance continues with a duet of hydrogen atoms entangled in a fusion reaction. We end back in the original scene, but this time with two fusion duets; one in the sun (on top of the machine), the other within a fusion reactor (on the floor). Less
My PhD research was on studying pairs of heavy-element reactions to see if there was a better way to make these isotopes. By shooting an io...
My PhD research was on studying pairs of heavy-element reactions to see if there was a better way to make these isotopes. By shooting an ion beam of a particular energy from an accelerator at a target and measuring the decays of the particular isotope we made in a detector further away, we can determine the reaction probability (cross section) of that reaction. The cross section is a ratio of the production rate of the thing you want to make by the beam dose per unit area by the number of target nuclei per unit area. If you make the same isotope two different ways and one way has a significantly higher cross section, it indicates a favored reaction. In my dissertation research I looked at eight different reactions, or four pairs, making the elements Db, Bh, Mt, and Rg. If you aren’t familiar with those elements, look at the bottom of the transition metals on the periodic table. nnThe cyclotron accelerates beam ions in an outwardly spiraling horizontal path. If you look closely you can see that the beam ball color and the target hoop color are combined in the hoop color of the product atom, most of the time. (I didn’t have any white LED beam balls.) I used t-shirts of different colors with their element symbols to show that the combination of the beam ball and target hoop made something completely different. The product atom recoils out of the target and travels along with unreacted beam and gets separated along the way to the detector. The decaying atom of Mt first undergoes alpha decay by getting rid of the yellow ball. The so-called “daughter” product Bh also decays by alpha emission to Db, but the Db atom grabs a red ball representing an electron and turns into Rf. This isotope of Rf spontaneously fissions – or splits in two – and that ends the decay chain. I used this same kind of experimental method to discover the new isotope 260Bh, which is so awesome I had to use fire to represent it.nnYou see eight “data points” towards the end of the video but I only list five reactions plus the new isotope because those are the ones I did myself. The other three data points were added to my results from a thorough meta-analysis of the literature. The short answer to the question of “is there a favored reaction method?” is NO. The statistical uncertainty in the cross sections of each reaction pair overlap, represented at the end by the rotating hoops.nnThanks for watching! Less
Quick Key:nNavy: electrons (e-)nBlue/Orange: ferrocenium / ferrocene (Fcn+/ Fcn)nRed: lithium ions (Li+)nYellow: solvent (Sol)nnnSide reacti...
Quick Key:nNavy: electrons (e-)nBlue/Orange: ferrocenium / ferrocene (Fcn+/ Fcn)nRed: lithium ions (Li+)nYellow: solvent (Sol)nnnSide reactions in lithium-ion batteries are a major problem for battery safety and lifetime. My research tries to determine what these side reactions are and how to control them. To do this, I developed a new method to characterize side reactions by using the molecule ferrocene. When ferrocene is in its reduced (electrically neutral) form, it is orange. When it is in the oxidized (positively charged) form, known as ferrocenium, it is blue-green.nnThe main reaction in this system is the reduction of lithium ions (red dancers). When lithium ions are reduced by electrons (navy blue dancers), the resulting lithium intercalates into the electrode. However, solvent molecules (yellow dancers) are reduced at the same potential. The insoluble solvent reduction products precipitate as a film on the electrode surface. This film passivates the electrode, blocking further reaction. nnSolvent reduction is much more complex than the single-electron reaction shown here, and the properties of such thin films are hard to measure. To better understand the films, we add ferrocenium (blue dancer). Because ferrocenium reduction occurs at a different potential than lithium or solvent reduction, its rate is much easier to measure. As the film grows thicker and less porous, through-film ferrocenium reduction becomes more difficult. This method can thereby determine film parameters such as the thickness and porosity.nnThis dance was performed with the help of Lindy on Sproul, our campus swing dance club. The song, "What'cha Know Joe?", reflects both the poorly-understood nature of side reactions and the mental state frequently experienced during a Ph. D. Less
Winner of the Biology category of Dance your PhD 2011 competition by Science journal. nnOur dance depicts the social and sexual behavior of ...
Winner of the Biology category of Dance your PhD 2011 competition by Science journal. nnOur dance depicts the social and sexual behavior of the common fruit fly and illustrates how male-male relatedness can reduce the intensity of male-male competition and affect female choice. Less
A dance with men in speedos portraying chicken sperm took the top prize in Science Magazine's annual 'Dance your Ph.D.' contest. Jen Markha...
A dance with men in speedos portraying chicken sperm took the top prize in Science Magazine's annual 'Dance your Ph.D.' contest. Jen Markham runs down all the top dances. Less
I created this video for the competition "Dance Your PhD," sponsored by Science and TED. nnThe aim of the contest is to get scientists to cr...
I created this video for the competition "Dance Your PhD," sponsored by Science and TED. nnThe aim of the contest is to get scientists to creatively explain their PhD theses through dance. I have a second goal, which is to show what "math research" means (since many people think it means looking up formulas in books).nnIn the first minute of this video, the dancer (Libby) shows how two pentagons are glued together to make a surface. This is the key idea of the video -- the explaining of science, wordlessly, through dance. You will understand it, and you will remember it. This is my favorite part!nnOkay, now step back for a minute. Imagine that you are walking in a straight line on a bagel. Maybe you walk right through the hole, and return back to where you started. Maybe you walk around the outside (like an equator), and return back to where you started. Or maybe you walk in a spiraling path (still in a straight line), through the hole and around the bagel a few times before returning to where you started.nnIn the next part of the video, Libby dances across the pentagon in a straight line. This is exactly like your spiraling walk on the bagel: she dances in a straight line, and goes around the surface a few times (maybe 8, because there are 8 lines on the pentagons) before she returns to where she started and repeats the path.nnWhen Libby dances across the pentagons in straight lines, she dances across the colored edges of the pentagons. We care about which ones she crosses, so we keep track of it by having a Math Hatter with that color shirt get in line. This creates a sequence of colors (which repeats with period 8).nnMy thesis investigates what happens to this color sequence when we change the pentagon surface. We "shear, cut and reassemble the pentagons," which is clearly shown in the video. This changes the original 8 lines on the pentagons to a different pattern -- 4 lines, as it turns out. When Libby dances across these four lines, she's doing a different, shorter spiral around the bagel (if you will). She crosses four colored edges, which gives us a new sequence of Math Hatters. Thesis question: What is the relationship between the 8-color sequence and the 4-color sequence?nnAnswer: Each Math Hatter checks to see if s/he has the same color on both sides, and if so, stays in line (keeps her hat), and if not, sadly has to leave (removes his hat).nnThat's my theorem: Shearing and reassembling the pentagons is equivalent to seeing if the colors are the same on both sides. nnMost videos submitted to this contest use metaphor: "I study titanium bonding to bone, which is kind of like titanium and bone dancing together." I am fortunate that I can show you the actual objects (shapes and lines) that I study, and explain the actual result I proved in my thesis.nnThanks for watching, and for reading this explanation.nnHere is the FAQ about how I created this video: https://vimeo.com/47273811nnThis video has been shown at:n- the AMS Math Research Community at Snowbird, UTn- the Summer@ICERM REU, Brown Universityn- the Anja S. Greer Math Conference at Phillips Exeter AcademynnAlso seen on:n- Reddit: http://www.reddit.com/r/math/comments/vx3wt/cutting_sequences_on_the_double_p...n- PhD + epsilon: http://blogs.ams.org/phdplus/2012/08/31/performance-math/n- Brown Daily Herald: http://www.browndailyherald.com/grad-student-illustrates-math-thesis-through-dance-1.2774229#n- BDH article (essentially) reported In Russian: http://blog.campus-online.ru/?p=1800n- The Aperiodical: http://aperiodical.com/2012/07/dance-your-phd-cutting-sequences-on-the-double...n- Math Munch: http://mathmunch.wordpress.com/2012/07/09/faces-blackboards-and-dancing-phds/n- AMS Graduate Student Blog: http://mathgradblog.williams.edu/dance-math-phd/n- howthebodyworks: http://howthebodyworks.org/post/30128065018/dance-your-thesis-by-diana-davis-is-the-firstn- Williams math headlines: http://math.williams.edu/diana-davis-07-phd-dance-video/n- Brown math headlines: http://www.math.brown.edu/nnIf you have read this far and you want to read the actual paper for which this video serves as a sort of abstract, here it is: http://www.math.brown.edu/~diana/math/VeechPolygons.pdfnYou can write to me at diana(at)math.brown.edu. Less
DJ FESTO STATION DANCE 13 TEMMUZ 2012 SET2
DJ Andi Best - Call me mister beat (Beta Release 0.937 Dance Touch Mix 2012) ...listen to other productions of Electric Synth Fashion on my ...
DJ Andi Best - Call me mister beat (Beta Release 0.937 Dance Touch Mix 2012) ...listen to other productions of Electric Synth Fashion on my YouTube channel. Let the music play... ... more music on my YouTube channel djandibest. Have a good time ;-) DJ Andi Best - Call me mister beat (Beta Release 0.937 Dance Touch Mix 2012) Composed by DJ Andi Best 2012 Mixed by DJ Andi Best 2012 Artist / Künstler : DJ Andi Best Using Equipment: Propellerhead Reason 4 Software,Fame Digital KX61C Midi Controller, Pioneer DJM-3000 Mixer, Magix Music Maker (for the video) DJ AT HOME STUDIO Germany July 2012 ELECTRIC SYNTH FASHION PRODUCTION Germany 2012 DJ Andi Best - Der Party-DJ für die Region zwischen Köln und Frankfurt - 70er - 80er - 90er - 2000er - Italo Disco - Disco - Rock - Dance - Techno - House - Charts - Discofox - Schlager - Karneval - Kölsche Lieder - Barjazz - Chillout - uvm. Geburtstag - Hochzeit - Vereinsfeier - Betriebsfest - Firmenevent - Promotion - Freundeparty - Themenabend - Loungenight - Willkommensparty - Sportfest - Verabschiedungsfeier - Afterworkparty - Summer Night Special - usw. Less
[V] D3 Dil Dosti Dance 19th July 2012 Video Watch Online Pt4
Latin Dance Mix - Summer 2012 by Dj Aris Music Contain : - Lavinia ft. Funky Djs - Loca - Don Omar - Taboo - Daddy Yankee - Lovumba - Luis V...
Latin Dance Mix - Summer 2012 by Dj Aris Music Contain : - Lavinia ft. Funky Djs - Loca - Don Omar - Taboo - Daddy Yankee - Lovumba - Luis Vazquez & Kato Jimenez ft. Jesus Sanchez - Dime Que Me Quieres - Don Omar & Lucenzo ft. Kryz Santana & Karmin Shiff - Sexo Kuduro - Les Jumo ft. Mohombi - Sexy - Sasha Lopez & Andreea D. ft. Broono - All My People - Gabriel Davi - Beautiful - Romano & Sapienza ft. Rodriguez - Tacata - Karmin Shiff ft. Juliana Pasini - Ole Ola Less
BORN TO DANCE Summer Camp 2012 hip-hop kids Klaudia Szok
So this is our Video Response for the Dance Olympic Campaign 2012 ! :D We had a lot of fun making the Video with our friends and our dreams ...
So this is our Video Response for the Dance Olympic Campaign 2012 ! :D We had a lot of fun making the Video with our friends and our dreams would come true, when we really could win this. *__* We love Golden Bomber because they're very funny and crazy... just like us sometimes. xD Have fun watching the Video. It's about how people can change, after something bad happened in their lifes. And also that you have the strenght in yourself, to get over it and be stronger ! :D Less
Kinsley's Preschool Dance Program May 2012 with Jess Dane and Act
Mix Electro House Dance Summer Party 2012 * 70 Min. de Musica para tus oidos d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ ...
Mix Electro House Dance Summer Party 2012 * 70 Min. de Musica para tus oidos d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ d-.-b/ MIX: 1- 130 LMFAO - SORRY FOR PARTY ROCKIG 2- 128 BPM Moves Like Jagger 3- 130 Rolling In The Deep - Adele ( Remix FT Alejandro Bootleg) 4- 128 US FALLIN' IN LOVE - USHER FT. PITBULL 5- 128 Paso - Sak Noel 6- 130. Lmfao ft Marron 5 - Party Like jagger [ DanGo Mashup ] 7- 130. Lmfao & Afrojack ft David Guetta & Usher Good Control You 8- 132 BEP - The Time Reedit 9- 134 LMFAO - Sorry For Party Rocking (RE-EDIT) 10- David Guetta Ft. Sia - Titanium (ReMix) 11- 130 Lmfao - Sexy and I Know It (Electro 2012) 12- Full ELectro - Levels Dj Diego Lira (( 2012)) 13- 128 Alexandra Stan - Mr. Saxo Dutch (VRemix) 14- 128 - Maroon 5 - Moves Like Jagger 15- 128 - Rihanna feat. Calvin Harris - We Found Love - Oritzadok 16- 128 Me enamore - EleCtro Dj Diego LIra 17- 127 Don Omar - Taboo ( Ft. Bross Dirty Remix) 18- 128 INNA HOT VS SUN IS UT 2O12 IN ACAPELLA 19- 128 Flo Rida - Good Feeling 20- 130 DON OMAR FEAT. LUCENZO - DANZA CUDURO (Intro demasiado coqeta)(ELECTRO) Full Fiesta Para que te diviertas y escuches con la mejor mezcla de Dj Diego SUSCRIBANCE ........................................................................... Less
Alicia took 3 different dance classes in 2012 this was her recital for the Cheer class
Primera clase de Pop Dance Ago-Dic 2012 ¡Gracias por su energía! Nos vemos el próximo sábado. NOTE : This video is just for creative and...
Primera clase de Pop Dance Ago-Dic 2012 ¡Gracias por su energía! Nos vemos el próximo sábado. NOTE : This video is just for creative and inspirational purposes only , NO COPYRIGHT INFRINGEMENT INTENDED Less
Watch Online D3 Dil Dosti Dance 13th August 2012 Full Episode Here www.vhungama.com
Watch Online D3 Dil Dosti Dance 14th August 2012 Full Episode Here www.vhungama.com
Choreology competing at World of Dance Bay Area 2012 under the youth division at the Solano Fairgrounds in Vallejo, CA. 1st: GRaVy Babies 2n...
Choreology competing at World of Dance Bay Area 2012 under the youth division at the Solano Fairgrounds in Vallejo, CA. 1st: GRaVy Babies 2nd: YSC 3rd: Trouble Makers 4th: Hungry Kidz 5th: Choreology Less
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