Review of: The Ethics of Reproductive Technology (Kenneth D. Alpern ed., Oxford University Press 1992)

Review of: The Ethics of Reproductive Technology (Kenneth D. Alpern ed., Oxford University Press 1992). Additional readings, glossary, introduction, notes, preface. LC 92-8252; ISBN 0-19-507435-1. [370 pp. Paper $19.95. 200 Madison Avenue, New York NY 10016.

Indian Gaming: Issues and Prospects

This article explains the evolution of Indian gaming from economic and social perspectives. Many of the political opportunities and threats to Indian gaming are examined, and current and future issues surrounding Indian gaming are further explored

Fiscal Paternalism and New England Cities: A Policy for the Year 2000

The following commentary explores the future of urban public finance by focusing on the fiscal ills of New England\u27s major cities. The impact of general revenue sharing, categorical grants, federal tax policy, state aid, and own-source city revenues is assessed in light of a city\u27s ability to support itself. The authors conclude that a pattern of fiscal paternalism — the past and present policies for annual financial assistance to narrow the expenditure-revenue budget gap — must be altered if cities are to enter the twenty-first century as fiscally stable governments capable of providing the necessary services for a varied constituency

Where two fractals meet: the scaling of a self-avoiding walk on a percolation cluster

The scaling properties of self-avoiding walks on a d-dimensional diluted lattice at the percolation threshold are analyzed by a field-theoretical renormalization group approach. To this end we reconsider the model of Y. Meir and A. B. Harris (Phys. Rev. Lett. 63:2819 (1989)) and argue that via renormalization its multifractal properties are directly accessible. While the former first order perturbation did not agree with the results of other methods, we find that the asymptotic behavior of a self-avoiding walk on the percolation cluster is governed by the exponent nu_p=1/2 + epsilon/42 + 110epsilon^2/21^3, epsilon=6-d. This analytic result gives an accurate numeric description of the available MC and exact enumeration data in a wide range of dimensions 2<=d<=6.Comment: 4 pages, 2 figure

Star copolymers in porous environments: scaling and its manifestations

We consider star polymers, consisting of two different polymer species, in a solvent subject to quenched correlated structural obstacles. We assume that the disorder is correlated with a power-law decay of the pair correlation function g(x)\sim x^{-a}. Applying the field-theoretical renormalization group approach in d dimensions, we analyze different scenarios of scaling behavior working to first order of a double \epsilon=4-d, \delta=4-a expansion. We discuss the influence of the correlated disorder on the resulting scaling laws and possible manifestations such as diffusion controlled reactions in the vicinity of absorbing traps placed on polymers as well as the effective short-distance interaction between star copolymers.Comment: 13 pages, 3 figure

Enhancing Robustness and Immunization in geographical networks

We find that different geographical structures of networks lead to varied percolation thresholds, although these networks may have similar abstract topological structures. Thus, the strategies for enhancing robustness and immunization of a geographical network are proposed. Using the generating function formalism, we obtain the explicit form of the percolation threshold $q_{c}$ for networks containing arbitrary order cycles. For 3-cycles, the dependence of $q_c$ on the clustering coefficients is ascertained. The analysis substantiates the validity of the strategies with an analytical evidence.Comment: 6 pages, 8 figure

Energetic neutron identification with pulse shape discrimination in pure CsI crystals

Pulse shape discrimination with pure CsI scintillators is investigated as a method for separating energy deposits by energetic neutrons and photons at particle physics experiments. Using neutron data collected near the European XFEL XS1 beam window the pulse shape discrimination capabilities of pure CsI are studied and compared to CsI(Tl) using near-identical detector setups, which were operated in parallel. The inelastic interactions of 100 MeV neutrons are observed to produce a slower scintillation emission in pure CsI relative to energy deposits from cosmic muons. By employing a charge-ratio method for pulse shape characterization, pulse shape discrimination with pure CsI is shown to be effective for identifying energy deposits from neutrons vs. cosmic muons, however, pure CsI was not able resolve the specific type of neutron inelastic interactions as can be done with CsI(Tl). Using pulse shape discrimination, the rate of energetic neutron interactions in a pure CsI detector is measured as a function of time and shown to be correlated with the European XFEL beam power. The results demonstrate that pulse shape discrimination with pure CsI has significant potential to improve electromagnetic vs. hadronic shower identification at future particle physics experiments

Good Windbreaks Help Increase South Dakota Crop Yields

The use of field windbreaks as a soil conservation practice in the Plains States has progressed steadily during the past 20 years. These plantings reward their owners with numerous benefits, including the reduction of wind currents, soil drifting, crop blowout, evaporation, transpiration, and control of drifting snow. In many cases they also provide protection for livestock and wildlife and produce wood products and fruit for home use. Many farmers have also observed increased crop yields in areas protected by windbreaks. Little research data are available on this phase. To get more information, employees of the Soil Conservation Service interviewed representative South Dakota farmers during the fall of 1954 to obtain firsthand results on the use of field windbreaks2 for increasing crop yields