This book is a systematic attempt to address the issue of fossilization in relation to a fundamental question in second language acquisition research, which is: why are learners, adults in particular, unable to develop the level of competence they have aspired to in spite of continuous and sustained exposure to the target language, adequate motivation to learn, and sufficient opportunity to practice?

This volume, as a sequel to Fossilization in Adult Second Language Acquisition by Han (2004), brings together a collection of most recent theoretical and empirical studies on fossilization, a classic problem of second language acquisition. It covers a wide range of perspectives and issues. The analyses discussed herein address key concerns of many second language researchers and teachers with regard to just how far anyone can go in learning a new language.

This digital document is an article from World of Earth Science, brought to you by Gale®, a part of Cengage Learning, a world leader in e-research and educational publishing for libraries, schools and businesses. The length of the article is 541 words. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser. A comprehensive guide to the concepts, theories, discoveries, pioneers, and issues relating to topics in earth science. Its encyclopedic approach offers entries that are written in easy to understand language.

-- J. Michael Parrish, Northern Illinois University

The “Gale Encyclopedia of Science” is written at a level somewhere between the introductory sources and the highly technical texts currently available. This six-volume set covers all major areas of science and engineering, as well as mathematics and the medical and health sciences, while providing a comprehensive overview of current scientific knowledge and technology. Alphabetically arranged entries provide a user-friendly format that makes the broad scope of information easy to access and decipher. Entries typically describe scientific concepts, provide overviews of scientific areas and, in some cases, define terms.

This digital document is an article from UXL Encyclopedia of Science, brought to you by Gale®, a part of Cengage Learning, a world leader in e-research and educational publishing for libraries, schools and businesses. The length of the article is 931 words. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser. This collection of entries covers major areas of science including: biology, genetics, microbiology, astronomy, chemistry, physics, engineering, technology, geology, weather, archaeology, psychology, mathematics, and medicine, and provides readers with a wide range of up-to-date, relevant, and accurate information.

This digital document is a journal article from Palaeogeography, Palaeoclimatology, Palaeoecology, published by Elsevier in 2005. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

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One important, and poorly understood, issue concerning the taphonomy of nonmineralizing organisms in Cambrian Burgess Shale-type deposits is the diagenetic pathways by which organisms have become exceptionally preserved. Scanning electron microscopy (SEM) analyses of exceptionally preserved fossils from the lower Cambrian Chengjiang deposit of China demonstrate that nonmineralized tissue is preserved in a variety of ways, and further suggest that there was some taxonomic control over the precipitation of authigenic minerals during early diagenesis. Organic preservation is limited to certain decay-resistant structures such as heavily sclerotized spines on the claws of anomalocaridids. Labile organic tissues of nearly all nonmineralizing animals, however, are preserved by thin films of diagenetic minerals. Microstructural studies, energy-dispersive X-ray (EDX) analyses, and elemental mapping of these minerals indicate that mineral films include apatite, pyrite, and Fe-rich aluminosilicates. The results support the assumption that early diagenetic mineralization such as phosphatization and pyritization played a key role in the preservation of nonmineralized organisms. Pyritization seems to be the most important process by which nonmineralizing Chengjiang organisms are preserved in exceptional condition. Precipitation of Fe-rich aluminosilicates, which occurred following pyritization, also played a role in the preservation of some Chengjiang fossils. Phosphatization in the Chengjiang Lagerstatte was evidently rare, and limited taxonomically or to animals having large masses of organic material.

This digital document is an article from World of Microbiology and Immunology, brought to you by Gale®, a part of Cengage Learning, a world leader in e-research and educational publishing for libraries, schools and businesses. The length of the article is 528 words. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser. Covers the concepts, theories, discoveries, and pioneers in microbiology and immunology, using a mix of traditional academic and topical articles, this title addresses current ethical, legal, and social issues with special emphasis given to biological warfare and terrorism.