"Empirical Studies in Industrial Organization" brings together leading scholars who present state-of-the-art research in the spirit of the structure-conduct-performance paradigm embodied in the work of Leonard W. Weiss. The individual chapters are generally empirically or public policy oriented. A number of them introduce new sources of data that, combined with the application of appropriate econometric techniques, enable new breakthroughs and insights on issues hotly debated in the industrial organization literature. For example, five of the chapters are devoted towards uncovering the link between market concentration and pricing behavior. While theoretical models have produced ambiguous predictions concerning the relationship between concentration and price, these chapters, which span a number of different markets and situations, provide evidence that a high level of market concentration tends to result in a higher level of prices. Three of the chapters explore the impact of market structure on production efficiency, and three other chapters focus on the role of industrial organization on public policy.

Local interstitial radiation therapy of intrinsic and inaccessible brain tumors is confronted with two major problems: 1. The tolerance of normal brain tissue, which is usually involved in local tumor irradiation, i.e. perifocal white matter edema and demyelinating effects, is crucial. 2. Data on radiation effects of implanted radioactive sources on neoplastic tissue, i.e. data on the radiosensitivity and on the biology of tumors, are still widely unavailable. In clinical practice the dose with which to achieve a given volume of tumor necrosis is roughly estimated. This report deals with the experimental findings of Iodine-125 and Iridium-I92 permanent implants in healthy and neoplastic brain tissue. Our own experimental findings are correlated with experimental data on Yttnul11-l)O irradiation from the literature. The study is directed to collect data on the tolerance non-tumoral brain tissue and to attempt to establish a dose-response relationship. Morphologic Changes in the Dog Brain Following Interstitial Iodine-125 Irradiation Iodine-I25 seeds (manufactured by 3 M Company, St. Paul, M. N.) with an activity of 3.55 mCi were permanently implanted under stereotactic conditions into the subcortical white matter of the gyrus coronalis of the left hemisphere in 6 beagle dogs. One animal with a non-radioactive seed implanted under similar operative conditions served as a control. The animals were allowed to survive 25, 46, 71, 94, 248, 368 days, respectively, after the implantation. The control animal survived 46 days. A detailed description of the experimental procedure is given elsewhere 16. 17.

The phenomenon of phantom limb was described in medical literature at least as early as 1545 by Ambroise Pare, according to the notes in the translation of Lemos' dissertation, "On the Continuing Pain of an Amputated Limb", by Price and Twombly [9]. This strange experience was brought to public attention by a popular essay anonymously published 1866 by Mitchell concerning the story of George Dedlow, a quadriamputee who described his invisible limbs [7]. In 1871 Mitchell wrote under his own name, and was the. first to use the term "phantom limb" [8]. In this work, he also corrected some erroneous beliefs that had arisen from his 1866 essay [13]. Most amputees report feeling a phantom limb almost immediately after amputation of an arm or a leg [11]. It is a positive sensation, usually described as tingling or numbness, which is not painful. The most distal parts of the limb, particulary the digits, thumb, and index, are the strongest and most persisting phantom sites, and may be the only parts to appear even after removal of a whole limb. The elbow or knee is sometimes involved, the forearm or lower leg rarely, and the upper arm and thigh almost never [5]. The phantom thus appears to consist predominantly of those parts which have the most extensive representa tion in the thalamus and in the cerebral cortex.

Better Living Through Economics consists of twelve case studies that demonstrate how economic research has improved economic and social conditions over the past half century by influencing public policy decisions. Economists were obviously instrumental in revising the consumer price index and in devising auctions for allocating spectrum rights to cell phone providers in the 1990s. But perhaps more surprisingly, economists built the foundation for eliminating the military draft in favor of an all-volunteer army in 1973, for passing the Earned Income Tax Credit in 1975, for deregulating airlines in 1978, for adopting the welfare-to-work reforms during the Clinton administration, and for implementing the Pension Reform Act of 2006 that allowed employers to automatically enroll employees in a 401(k). Other important policy changes resulting from economists' research include a new approach to monetary policy that resulted in moderated economic fluctuations (at least until 2008!), the reduction of trade impediments that allows countries to better exploit their natural advantages, a revision of antitrust policy to focus on those market characteristics that affect competition, an improved method of placing new physicians in hospital residencies that is more likely to keep married couples in the same city, and the adoption of tradable emissions rights which has improved our environment at minimum cost.