Combining historical research with a lucid explication of archaeological methodology and reasoning, Measuring Time with Artifacts examines the origins and changing use of fundamental chronometric techniques and procedures and analyzes the different ways American archaeologists have studied changes in artifacts, sites, and peoples over time. In highlighting the underpinning ontology and epistemology of artifact-based chronometers?cultural transmission and how to measure it archaeologically?this volume covers issues such as why archaeologists used the cultural evolutionism of L. H. Morgan, E. B. Tylor, L. A. White, and others instead of biological evolutionism; why artifact classification played a critical role in the adoption of stratigraphic excavation; how the direct historical approach accomplished three analytical tasks at once; why cultural traits were important analytical units; why paleontological and archaeological methods sometimes mirror one another; how artifact classification influences chronometric method; and how graphs illustrate change in artifacts over time. An understanding of the history of artifact-based chronometers enables us to understand how we know what we think we know about the past, ensures against modern misapplication of the methods, and sheds light on the reasoning behind archaeologists' actions during the first half of the twentieth century.

This volume emphasizes one aspect of scientific method: units of measure and their construction as applied to archaeology. Attributes, artifact classes, locational designations, temporal periods, sampling universes, culture stages, and geographic regions are all examples of constructed units.

Magnetic resonance imaging (MRI) has become the leading cross-sectional imaging method in clinical practice. Continuous technical improvements have significantly broadened the scope of applications. At present, MR imaging is not only the most important diagnostic technique in neuroradiology and musculoskeletal radiology, but has also become an invaluable diagnostic tool for abdominal, pelvic, cardiac, breast and vascular imaging. This book offers practical guidelines for performing efficient and cost-effective MRI examinations in daily practice. The underlying idea is that, by adopting a practical protocol-based approach, the work-flow in a MRI unit can be streamlined and optimized. For the second edition, all chapters have been thoroughly reviewed, and new techniques and figures were included. This book will help beginners to advance their starting point in implementing the protocols and will aid more experienced users in updating their knowledge.

It is difficult for today's students of archaeology to imagine an era when chronometric dating methods were unavailable. However, even a casual perusal of the large body of literature that arose during the first half of the twentieth century reveals a battery of clever methods used to determine the relative ages of archaeological phenomena, often with considerable precision. Stratigraphic excavation is perhaps the best known of the various relative-dating methods used by prehistorians. Although there are several techniques of using artifacts from superposed strata to measure time, these are rarely if ever differentiated. Rather, common practice is to categorize them under the heading `stratigraphic excavation'. This text distinguishes among the several techniques and argues that stratigraphic excavation tends to result in discontinuous measures of time - a point little appreciated by modern archaeologists. Although not as well known as stratigraphic excavation, two other methods of relative dating have figured important in Americanist archaeology: seriation and the use of index fossils. The latter (like stratigraphic excavation) measures time discontinuously, while the former - in various guises - measures time continuously. Perhaps no other method used in archaeology is as misunderstood as seriation, and the authors provide detailed descriptions and examples of each of its three different techniques. Each method and technique of relative dating is placed in historical perspective, with particular focus on developments in North America, an approach that allows a more complete understanding of the methods described, both in terms of analytical technique and disciplinary history. This text will appeal to all archaeologists, from graduate students to seasoned professionals, who want to learn more about the backbone of archaeological dating.

Magnetic resonance imaging (MRI) is the most technically dependent imaging technique in radiology. To perform and interpret MRI studies correctly, an understanding of the basic underlying principles is essential. Understanding Magnetic Resonance Imaging explains the pulse sequences, imaging options, and coils used to produce MR images, providing a strong foundation for performing and interpreting imaging studies. The text is complemented by more than 100 figures and 25 photomicrographs illustrating the techniques discussed. Radiology residents, MR technologists, and radiologists should not be without Understanding Magnetic Resonance Imaging-the only single resource that explains all technical aspects of MRI, including recent advances, and presents all imaging options.