SEM image of open cell polyurethane foam
If a gas is injected into a liquid it forms a cellular foam structure. When a thermoset prepolymer of low viscosity is foamed, the polymer can drain from the cell walls (driven by surface tension) before it sets at the cell edges, leaving an open-celled foam. The cell edges have three concave sides, giving rise to the tri-cuspid cross section visible at the bottom of this image. The average co-ordination number for the nodes (where struts meet) is four, giving tetrahedral junctions.
Author(s): DoITPoMS, University of Cambridge,J A Curran, Depa

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Challenges Families Face
OpenStax College
Understand the social and interpersonal impact of divorce Describe the social and interpersonal impact of family abuse
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Mapping and Its Discontents: Katharine Harmon, Rebecca Solnit, Dana Cuff
Katharine Harmon at 6:47 Rebecca Solnit at 29:08 Dana Cuff at 53:05 Maps are also a form of narrative and a form of art. In this video, Katharine Harmon, author of The Map as Art, discusses how narrative contents create maps, and set up the vocabulary of maps. ""Maps come when narrative is not enough, or the opposite, narrative comes when the map is not enough."" Rebecca Solnit, author of Unfathomable City and Infinite City, discusses the making of maps as a way of knowing places. ""I love maps
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5.4 Product champion

Throughout the development of this innovation Edison endeavoured, by means of persuasive argument and demonstrations of progress, to convince those people who were in a position to help further the success of the electric light that it had great potential. These people included financiers who could provide capital for more research and development, industrialists who might install it in their factories, and politicians who might agree to the large-scale city installation of a lighting system.
Author(s): The Open University

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The Stuff of Genius: Copier
Before the invention of the modern copier, companies across the world
depended on time-consuming -- and, often, incorrect -- duplication
methods. This 2:20 video explains how the copier was invented and also how the inventor worked hard to develop this invention.

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How To Get Started With a College Savings Plan
This video is suitable for high school students and provides step-by-step instructions for starting a college savings plan. (2:30)
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Build-A-Word - Log
In this short cartoon clip from "WordWorld", the WordFriends use the letters L, O, and G, to build the word  "log."  After the word is built, it transforms into a log made of the letters used. (1:12)
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International Space Station captures new HD images of Earth
Subscribe: http://smarturl.it/reuterssubscribe NASA releases new images of Earth after it tests its new high definition cameras from the exterior of the International Space Station. Jillian Kitchener reports. Subscribe: http://smarturl.it/reuterssubscribe More Breaking News: http://smarturl.it/BreakingNews Reuters tells the world's stories like no one else. As the largest international multimedia news provider, Reuters provides coverage around the globe and across topics including business, f
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Venice Carnival kicks off with spectacle for the senses
A magical night-time spectacle inspired by Italian food and art kicks off the two week-long Venice Carnival. Gavino Garay reports. Subscribe: http://smarturl.it/reuterssubscribe More updates and breaking news: http://smarturl.it/BreakingNews Reuters tells the world's stories like no one else. As the largest international multimedia news provider, Reuters provides coverage around the globe and across topics including business, financial, national, and international news. For over 160 years, Reu
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Obama tells Congress U.S. deploying up to 275 troops to Iraq
Subscribe: http://smarturl.it/reuterssubscribe President Barack Obama tells Congress the U.S. is deploying up to 275 military personnel to Iraq as support and security for U.S. interests, as militants seize control of the north of the country. Mana Rabiee reports. Subscribe: http://smarturl.it/reuterssubscribe More Breaking News: http://smarturl.it/BreakingNews Reuters tells the world's stories like no one else. As the largest international multimedia news provider, Reuters provides coverage
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3.7 Protein phosphatases

Together with inositolphospholipid phosphatases, protein phosphatases are key regulators of signal transduction pathways. Like protein kinases, protein phosphatases are either tyrosine phosphatases (the majority of protein phosphatases, some of which are shown in Figure 44) or serine–threonine phosphatases (including the phosphoprotein phos
Author(s): The Open University

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IPICK - Selecting Books that are "Just Right!"
When we are selecting books to read in our 2nd grade classroom, we remember the acronym, I PICK. Listen are we explain what each letter means. (1:57)
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Cold War: Red China - part 4/5
1949 - 1972 Chinese communists win the longest civil war in 20th century history. Mao's land reforms are popular but in 1958, he embarks on a series of catastrophic changes. China maintains an incrasingly uneasy relationship with the Soviet Union. In 1960, the Sino-Soviet split paves the way for President Nixon's historic visit to Beijing.
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Cost of Capitalism - China
October 2004 China's spectacular economic growth has come at a heavy price. Millions of workers have been crippled in unsafe sweatshops. Part of this video is about one particulat man and the help that he got from a lawyer to get compensation for a work-related loss of his hand.

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20/20 Fidel Castro Interview - Barbara Walters [6 of 6]
Barbara Walters interviews Fidel Castro from Havana, Cuba, 25 years after her first interview with the Cuban leader. Her original interview made a little history because people got their first real look at the man. Although Castro is known for very long speeches, he rarely does interviews. Fidel Castro, 76 at the time of this interview, has outlasted nine US presidents. His rule continues to inspire both fear and devotion. He tells Barbara Walters that Soviet leader Nikita Khrushchev lied t
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2.3.2 Salinity, desiccation and biotic interactions on seashores

Tidal movements ensure that sea-shore habitats are, if not covered by seawater for part of each day, at least subject to spray-borne salt and wind. So, even well above the level of high tides, sea-shore organisms need to be more tolerant of salt than most terrestrial organisms. However, salinity (the concentration of salts dissolved in water) is not the only factor affecting sea-shore species. Seaweeds and shelled animals like limpets and barnacles are adapted to living in a highly saline mar
Author(s): The Open University

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Literary Festival 2013: Philosophy by Podcast [Audio]
Speaker(s): David Edmonds, Nigel Warburton | In the 5th century BC Socrates brought philosophy to the marketplace. Can this ancient branch of learning be rejuvenated by the technology of the 21st century? Philosophy Bites Back is the second book from the team that brings you Philosophy Bites, the hugely successful podcast that has now had 16 million downloads. Philosophy Bites Back is a collection of conversations with leading scholars on major figures in the history of philosophy. David Edmonds
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7.342 Cancer Biology: From Basic Research to the Clinic (MIT)
This course is one of many Advanced Undergraduate Seminars offered by the Biology Department at MIT. These seminars are tailored for students with an interest in using primary research literature to discuss and learn about current biological research in a highly interactive setting. In 1971, President Nixon declared the "War on Cancer," but after three decades the war is still raging. How much progress have we made toward winning the war and what are we doing to improve the f
Author(s): Kim, Carla,Haigis, Kevin

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Content within individual OCW courses is (c) by the individual authors unless otherwise noted. MIT OpenCourseWare materials are licensed by the Massachusetts Institute of Technology under a Creative C

11.3 Frequency selectivity

In preceding sections we examined two ways in which the auditory system may code frequency information: the place theory and phase locking. In this section we will look at the psychophysical evidence for place coding on the basilar membrane by examining the ability of the auditory system to resolve the components of sinusoidal waves in a complex sound – a phenomenon known as frequency selectivity.

The perception of a sound depends not only on its own frequency and intensity but also o
Author(s): The Open University

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Animoto
This video shows the viewer one of the Internet's best-kept secrets: Animoto.com. Say 'goodbye' to boring slideshows and 'hello' to dazzling videos.  A video can be created with a one-click upload if all your images  are saved in the same folder.  A very easy and fun way to create professional looking videos.
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