Parabolic beach marks on a polystyrene fracture surface
The fracture surfaces are generally very sharp and angular, indicating fast, brittle fracture with little ductile tearing. Parabolic 'beach marks', can be seen where the fracture has grown at a speed comparable to the speed of sound in the material. This results in periodic, momentary arrests in the crack propagation and periodic ridges in the fracture surface as it advances. These indicate the direction in which the fracture has occurred. Inside the beach marks is a disc-shaped flat region wher
Author(s): J A Curran, Department of Materials Science and Me

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Beach marks on a polystyrene fracture surface
The fracture surfaces are generally very sharp and angular, indicating fast, brittle fracture with little ductile tearing. 'Beach marks', can be seen where the fracture has grown at a speed comparable to the speed of sound in the material. This results in periodic, momentary arrests in the crack propagation and periodic ridges in the fracture surface as it advances. There is also evidence of the fracture surface branching onto different planes as it progresses.
Author(s): J A Curran, Department of Materials Science and Me

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Fracture surface in polystyrene
The fracture surfaces are generally very sharp and angular, indicating fast, brittle fracture with little ductile tearing. Parabolic 'beach marks', can be seen where the fracture has grown at a speed comparable to the speed of sound in the material (and has thus been periodically arrested) and indicate the direction in which the fracture has occurred. In places, there is evidence of ductile tearing, and also a finely fibrous surface which is the remnant of crazes. There is also some evidence of
Author(s): J A Curran, Department of Materials Science and Me

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Tetragonal Zirconia Polycrystals (TZP)
The comparatively low sintering temperature allows very fine grained (sub-micron), dense and so high strength as well as tough ceramics to be produced. The microstructure shows equiaxed, fine grains with little evidence of weakening grain boundary phases. Such microstructures have some of the highest values of toughness achieved in ceramics.
Author(s): Prof W E Lee, Department of Engineering Materials,

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Archaeology of Medieval and Tudor Britain
The aim of this course is to provide a broad understanding of the archaeology of Britain in the period c. 1066-1600. Although the bulk of the material will relate to England and Wales, occasional reference will be made to Scotland and Ireland. The course takes a necessarily broad approach to the archaeology of the period. Although the treatment of excavated data will form an important component of the syllabus, other types of evidence will also be considered. For instance, the course will examin
Author(s): University of Exeter

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Town and Country in Roman Britain
This course aims to look at the archaeology of various types of urban centres in the province of Britannia Roman Britain and the settlements in the rural areas around them. In particular we will examine the inter-dependence and possible relationships of towns and countryside. We cannot ignore the fact that Britain was only one small province of an Empire which stretched from Asia Minor to Scotland and the Sahara Desert to the rivers Rhine and Danube. We may therefore occasionally have to conside
Author(s): University of Exeter

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5.4.2 When to evaluate accessibility

Technical and usable accessibility should be evaluated throughout the design life cycle, just as general usability should be. As with usability, the earlier in the process accessibility is evaluated the more likely the final product will be both technically and usably accessible. Accessibility can be evaluated or tested in early ideas and paper designs as well as prototype systems, and different aspects of accessibility can be evaluated at these different stages. For example, the general acce
Author(s): The Open University

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Plant Protection Measures in Specialised Cultivation. Conference on Organic Cultivation. "Specialise

Scientific Conference, national, lfz Raumberg-Gumpenstein (Austria, 2009), 33 slides
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Honey

pdfCompilation of seasonal recipes by Bio Austria (Austrian organization of organic farmers) provided by www.gutessen.at
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Key mapping in Ableton Live
Learn more about Loudon's Advanced Music Production with Ableton online course: http://bit.ly/1qz0UAW In this video, Berklee Asst. Professor and Berklee Online course author Loudon Stearns explores Ableton Live keyboard commands and custom keyboard mapping
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Legislative hearing on redlining practices
Hope Kelly reports on a legislative hearing in Boston on alleged redlining practices by Boston banks. Kelly reports that the Federal Reserve Bank released a study finding evidence of redlining practices. Kelly notes that the banking industry reacted strongly to the accusations. Kelly's report includes footage from the legislative hearings. Barney Frank (US Congressman) and Benjamin Hooks (Executive Director, NAACP) condemn redlining practices. Richard Pollard (Chairman, Massachusetts Banking Ass
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"A Sweepstakes Attracts Attention": Corporate Executives Defend Sweepstakes Promotions
In the 1960s, lottery-like contests designed to publicize products through sweepstakes competitions spread rapidly. In the 19th century, every state banned lotteries--defined as competitions in which chances to win prizes were sold÷to protect citizens. In 1868, Congress prohibited the distribution of lottery materials through the mail. The mid-20th century sweepstakes, however, did not require contestants to purchase tickets or products to win prizes and were thus considered legal. In 1966, the
Author(s): Center for History and New Media/American Social H

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Serious Questions of Fairness, Ethics, and Legality: Congress Investigates Sweepstakes Promotions
In the 1960s, lottery-like contests designed to publicize products through sweepstakes competitions spread rapidly. In the 19th century, every state banned lotteries--defined as competitions in which chances to win prizes were sold--to protect citizens. In 1868, Congress prohibited the distribution of lottery materials through the mail. The mid-20th century sweepstakes, however, did not require contestants to purchase tickets or products to win prizes and were thus considered legal. In 1966, the
Author(s): Center for History and New Media/American Social H

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A Gallery of Institutional Projects
This pilot effort between the two foundations is designed to help institutions and programs create succinct project portals that provide quick access to a project overview and selected instruments, materials, data and evidence related to their work.
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Learning From Cases
This site focuses on the use of case writing to support student learning in a Foundations of Learning course for pre-service teachers at the graduate level. It uses a course timeline to organize links that show course materials, the development of one student's case, and student and instructor reflections. The site index also includes an archive of students' cases, as well as a collection of other course materials.
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Learning Interdisciplinarity: A Course Portfolio
Linkon's research focused on evaluating the effectiveness of her incremental learning assignments in an interdisciplinary course. She gathered a variety of kinds of evidence of students' learning, ranging from surveys and interviews to students' projects and her own reflections. The three-assignment incremental learning sequence worked well for most students. Linkon's analysis of their work showed a clear development of analytical complexity in their writing over the course of the term. Students
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Making Sense of Complementary and Alternative Medicine: Analysis of a Family Nurse Practitioner Prog
The overall goal of this inquiry project was to evaluate approaches to incorporating complementary and alternative medicine into the curricula of nurse practitioner (NP) programs. Specifically, Burman undertook a comprehensive assessment of how the concept of complementary and alternative therapies is (or is not) addressed in her FNP curriculum. The outcome of this assessment is a 'curriculum component portfolio' with selected pieces of evidence, critical reflection and recommendations.
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Growth of Cities
Cities up and down the state of California grew rapidly during the Gold Rush era. Some of these cities were veritable boomtowns: San Francisco, a small village in 1847, was a bustling city by 1849, just two years later. San Francisco's population boom even had an impact on its geography. One image from 1847 shows Montgomery Street on the waterfront; but a photograph taken in 1862 shows that the waterfront had been filled to increase the city's real estate, pushing Montgomery Street inland. South
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American Journeys
Everything teachers and students need for a successful National History Day project is available at this site -- topic ideas, lesson plans, research advice, and thousands of pages of fully indexed eyewitness accounts of North American exploration. Follow famous explorers. Witness first contacts between cultures. See how the exchange of goods and ideas forever altered people's daily life and ideas. Find out what "America" meant to the people who arrived here long ago and to the people who greeted
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Developing the Theory: Continental Drift
This document outlines the development of the theory of continental drift and how many lines of evidence collected over several decades by various researchers were brought together to explain how the seafloor spreads and the continents move about. Links to additional information are included.
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