Yi sheng yi meng yi xiang zhi

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author, Andrew Langley

An introduction to the grasslands of the world, from tropical Africa to the Arctic Circle, and the many animals, big and small, that inhabit them.

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Cristina Kessler

Miss B. takes her students on a field trip to Great Pond Bay on St. Croix to wait for a little bird, a whimbrel named Hope, and teach them about the amazing journey Hope makes each year and the importance of protecting her habitats. Includes readers' guide, fun facts, and more.

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Maurizio Gasperini

<p>This reference textbook is an up-to-date and self-contained introduction to the theory of gravitational interactions. The first part of the book follows the traditional presentation of general relativity as a geometric theory of the macroscopic gravitational field. A second, advanced part then discusses the deep analogies (and differences) between a geometric theory of gravity and the gauge theories of the other fundamental interactions. This fills a gap which is present in the context of the traditional approach to general relativity, and which usually makes students puzzled about the role of gravity. The necessary notions of differential geometry are reduced to the minimum, leaving more room for those aspects of gravitational physics of current phenomenological and theoretical interest, such as the properties of gravitational waves, the gravitational interactions of spinors, and the supersymmetric and higher-dimensional generalization of the Einstein equations. Theory of Gravitational Interactions will be of particular value to undergraduate students pursuing a theoretical or astroparticle curriculum. It can also be used by those teaching related subjects, by PhD students and young researchers working in different scientific sectors but wishing to enlarge their spectrum of interests, and, in general, by all scholars interested in the modern aspects and problems of gravitational interaction.</p>

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retold by Carl Bowen

Scientist Pierre Aronnax and his trusty servant set sail to hunt a sea monster. With help from the world’s greatest harpooner, the men discover that the creature is really a high-tech submarine with a mysterious leader, Captain Nemo.