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Seismic observations show the Earth's inner core has significant and unexplained variation in seismic attenuation with position, depth and direction. Interpreting these observations is difficult without knowledge of the visco‐ or anelastic dissipation processes active in iron under inner core conditions. Here, a previously unconsidered attenuation mechanism is observed in zinc, a low pressure analog of hcp‐iron, during small strain sinusoidal deformation experiments. The experiments were performed in a deformation‐DIA combined with X‐radiography, at seismic frequencies (∼0.003–0.1 Hz), high pressure and temperatures up to ∼80% of melting temperature. Significant dissipation (0.077 ≤ Q−1(ω) ≤ 0.488) is observed along with frequency dependent softening of zinc's Young's modulus and an extremely small activation energy for creep (⩽7 kJ mol−1). In addition, during sinusoidal deformation the original microstructure is replaced by one with a reduced dislocation density and small, uniform, grain size. This combination of behavior collectively reflects a mode of deformation called “internal stress superplasticity”; this deformation mechanism is unique to anisotropic materials and activated by cyclic loading generating large internal stresses. Here we observe a new form of internal stress superplasticity, which we name as “elastic strain mismatch superplasticity.” In it the large stresses are caused by the compressional anisotropy. If this mechanism is also active in hcp‐iron and the Earth's inner‐core it will be a contributor to inner‐core observed seismic attenuation and constrain the maximum inner‐core grain‐size to ≲10 km. Plain Language Summary The Earth's inner‐core is the most remote and inaccessible part of our planet. Knowledge of the inner‐core's structure comes from interpretation of the information held in seismic waves that have passed through the inner‐core. These waves show measurable variation in wave speed and damping with depth. To investigate the wave damping in the inner‐core we performed experiments that mimicked the passage of seismic waves through zinc. Zinc was used as a low‐pressure analog because it has the same crystallographic structure as the iron in the inner‐core. In these experiments, we observed new behavior in the zinc samples that can only be explained by the behavior of different directions within the zinc crystal lattice. These we named “elastic strain mismatch superplasticity” and if the same phenomena occurs in the Earth's inner‐core it could explain the seismic observations. Key Points Zinc, a low pressure analog for hcp‐iron, deforms by internal stress superplasticity during small amplitude sinusoidal‐strain deformation Internal stress superplasticity due to mechanical oscillations has not been previously reported Internal stress superplasticity is another attenuation mechanism that could be active in the Earth's inner‐core

We developed a stress sensor for in-situ deformation experiments using synchrotron radial X-ray diffraction. This stress sensor provided nearly diffraction-plane-independent stress that, when used in series with a sample, reduced the uncertainty of the average stress estimation acting on a sample. Here, we present the results of a study where pyrope was used as a stress sensor. Using a Deformation-DIA (D-DIA) high-pressure deformation apparatus, pyrope, olivine and alumina were deformed in the same run/cell assembly placed in series along the compression direction. Deformation experiments were conducted at pressures between 4 and 5 GPa and temperatures between 730 and 1273 K with strain-rates between 10−5 and 10−6 s−1. Stresses estimated from various (hkl) planes in pyrope were nearly the same; i.e., pyrope is plastically isotropic with ≤10 % variation with (hkl). However, stresses from various (hkl) planes in olivine and alumina varied by approximately a factor of 3. Comparisons between average stresses inferred from pyrope and those from different diffraction planes in olivine and alumina showed that the average stress in these materials evolved from low-end stress, estimated from various (hkl) planes at small strain, to high-end stress at a large strain. This suggests that the rate-controlling slip system in these materials changes from the soft to the hard slip system with strain.

We report results from axisymmetric deformation experiments carried out on forsterite aggregates in the deformation-DIA apparatus, at upper mantle pressures and temperatures (3.1–8.1 GPa, 1373–1673 K). We quantified the resulting lattice preferred orientations (LPO) and compare experimental observations with results from micromechanical modeling (viscoplastic second-order self-consistent model—SO). Up to 6 GPa (~185-km depth in the Earth), we observe a marked LPO consistent with a dominant slip in the (010) plane with one observation of a dominant [100] direction, suggesting that [100](010) slip system was strongly activated. At higher pressures (deeper depth), the LPO becomes less marked and more complex with no evidence of a dominant slip system, which we attribute to the activation of several concurrent slip systems. These results are consistent with the pressure-induced transition in the dominant slip system previously reported for olivine and forsterite. They are also consistent with the decrease in the seismic anisotropy amplitude observed in the Earth’s mantle at depth greater than ~200 km.

Examining the 1950s debate over the media and juvenile delinquency, this study shows how the development of youth culture and the rise of a mass-media society became intertwined and confused.

\"Guardians of Power ought to be required reading in every media college. It is the most important book about journalism I can remember.\" John Pilger \"Regular critical analysis of the media, filling crucial gaps and correcting the distortions of ideological prisms, has never been more important. Media Lens has performed a major public service by carrying out this task with energy, insight, and care.\" Noam Chomsky \"Media Lens is doing an outstanding job of pressing the mainstream media to at least follow their own stated principles and meet their public service obligations. [This is] fun as well as enlightening.\" Edward S. Herman Can a corporate media system be expected to tell the truth about a world dominated by corporations? Can newspapers, including the 'liberal' Guardian and the Independent, tell the truth about catastrophic climate change -- about its roots in mass consumerism and corporate obstructionism -- when they are themselves profit-oriented businesses dependent on advertisers for 75% of their revenues? Can the BBC tell the truth about UK government crimes in Iraq when its senior managers are appointed by the government? Has anything fundamentally changed since BBC founder Lord Reith wrote of the establishment: \"They know they can trust us not to be really impartial\"? Why did the British and American mass media fail to challenge even the most obvious government lies on Iraqi weapons of mass destruction before the invasion in March 2003? Why did the media ignore the claims of UN weapons inspectors that Iraq had been 90-95% \"fundamentally disarmed\" as early as 1998? This book answers these questions, and more. Since July 2001, Media Lens has encouraged thousands of readers to email senior editors and journalists, challenging them to account for their distorted reporting on Iraq, Afghanistan, Kosovo, Haiti, East Timor, climate change, Western crimes in Central America, and much more. The responses -- often surprising, sometimes outrageous -- reveal the arrogance, unaccountability and servility to power of even our most respected media.

This indispensible volume reviews outstanding European, American and Australian research in the cognitive, social and cultural implications of writing for digital media. It addresses writing modes and environments, writing and communication, digital tools for writing research, online educational environments, and social and philosophical aspects.

Government interventions in media markets are often criticized for preventing audiences from getting the media products they want. A free press is often asserted to be essential for democracy. The first point is incorrect and the second is inadequate as a policy guide. Part I of this book shows that unique aspects of media products prevent markets from providing for audience desires. Part II shows that four prominent, but different, theories of democracy lead to different conceptions of good journalistic practice, media policy, and proper constitutional principles. Part II makes clear that the choice among democratic theories is crucial for understanding what should be meant by free press. Part III explores international free trade in media products. Contrary to the dominant American position, it shows that Parts I and II's economic and democratic theory justify deviations from free trade in media products.

Containing almost 200 entries from 'accountability' to the 'Westminster model' the Encyclopedia of Democratic Thought explores all the ideas that matter to democracy past, present and future. It is destined to become the first port-of-call for all students, teachers and researchers of political science interested in democratic ideas, democratic practice, and the quality of democratic governance. The Encyclopedia provides extensive coverage of all the key concepts of democratic thought written by a stellar team of distinguished international contributors. The Encyclopedia draws on every tradition of democratic thought, as well as developing new thinking, in order to provide full coverage of the key democratic concepts and engage with their practical implications for the conduct of democratic politics in the world today. In this way, it brings every kind of democratic thinking to bear on the challenges facing contemporary democracies and on the possibilities of the democratic future. The Encyclopedia is global in scope and responds in detail to the democratic revolution of recent decades. Referring both to the established democratic states of Western Europe, North America and Australasia, and to the recent democracies of Latin America, Eastern and Central Europe, Africa and Asia, classical democratic concerns are related to new democracies, and to important changes in the older democracies. Supplemented by full bibliographical information, extensive cross-referencing and suggestions for further reading, the Encyclopedia of Democratic Thought is a unique work of reference combining the expertise of many of the world's leading political scientists, political sociologists and political philosophers. It will be welcomed as an essential resource for both teaching and for independent study, and as a solid starting point both for further research and wider exploration.

The mass media in different countries reflects dominant concerns of contemporary societies. Ideas of `environmentalism' are often broad and imprecise, holding neither meaning nor currency. Environmentalism and Mass Media sheds new light on the diverse ideas of `environmentalism', the way environmental ideas circulate, and public reaction to environmental concerns conveyed by the media. Drawing on unique interviews with journalists, media pictures, and public opinion surveys in both UK and India, the authors outline the differing cultural, religious and political contexts against which `world views' form present a fascinating picture between North and South. Mass media and communication technology is in danger of locking Northern countries into a ghetto of environmental self-deception, thereby perpetuating poverty in the South. The South's goal remains the attainment of development; the North sees `environmental' problems occuring `elsewhere' - in Eastern Europe and developing countries. Whether or not `environmentalism' becomes a universal cause depends on how and to what extent such sharply contrasting world views can converge. Graham Chapman is Professor of Geography, lancaster University; Keval Kumar is a Reader in the Department of Communication and Journalism, University of Poona, India; Caroline Fraser is an Independent Media Consultant and Broadcast News Editor, Lyons, France; Ivor Gaber is Professor of Communications, Goldsmith College, London.