B-field Determination from Magnetoacoustic Oscillations in kHz QPO Neutron Star Binaries: Theory and Observations

We present a method for determining the B-field around neutron stars based on observed kHz and viscous QPO frequencies used in combination with the best-fit optical depth and temperature of a Comptonization model. In the framework of the transition layer QPO model, we analyze magnetoacoustic wave formation in the layer between a neutron star surface and the inner edge of a Keplerian disk. We derive formulas for the magnetoacoustic wave frequencies for different regimes of radial transition layer oscillations. We demonstrate that our model can use the QPO as a new kind of probe to determine the magnetic field strengths for 4U 1728-42, GX 340+0, and Sco X-1 in the zone where the QPOs occur. Observations indicate that the dependence of the viscous frequency on the Keplerian frequency is closely related to the inferred dependence of the magnetoacoustic wave frequency on the Keplerian frequency for a dipole magnetic field. The magnetoacoustic wave dependence is based on a single parameter, the magnetic moment of the star as estimated from the field strength in the transition layer. The best-fit magnetic moment parameter is about (0.5-1)x 10^{25} G cm^3 for all studied sources. From observational data, the magnetic fields within distances less 20 km from neutron star for all three sources are strongly constrained to be dipole fields with the strengths 10^{7-8} G on the neutron star surface.Comment: 10 pages, 1 figure, accepted for the Astrophysical Journal Letter

Strengthening the Pipeline— Talent Management for Libraries: A Human Resources Perspective

In order to both increase the pipeline of new librarians and develop “bench strength” (which is a human resources term used to refer to the capabilities and readiness of potential successors to move into key professional and leadership positions), librarians of color can work to form and develop strong, sustaining professional networks (in and outside the employing library) in order to help navigate the hiring process and to develop a support network that can be utilized throughout a professional career

The Elusiveness of Rural Development Theory and Policy: Domestic and Third World Perspectives Joined

Rural development in both the Third World and the United States suffers from many perceived failures and the lack of a theoretically rich conceptual framework by which effective rural development policies can be fashioned. Drawing upon Third World development literature, a perspective for domestic rural development is suggested. Development is defined by interdependence of increasingly specialized resources in production and the interdependence of relations among differentiated social groups including the rural disadvantaged. Effective programs must expand both resource utilization and restructure social relations that hinder development

Experimental investigation of the interaction of an intense relativistic electron beam with a plasma

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Do Students Effectively Monitor Their Comprehension?

This research is a preliminary investigation of students\u27 awareness of their performance on comprehension tasks at reconstructive and constructive levels. After comprehension instruction, students were asked reconstructive and constructive level comprehension questions and asked to rate their performance on each level of questions. Students rated their performance higher than they actually performed on both levels of questions. They also rated their performance the same on the two levels of questions, although their performance on reconstructive questions was higher than on constructive questions

Optically nonlinear energy transfer in light-harvesting dendrimers

Dendrimeric polymers are the subject of intense research activity geared towards their implementation in nanodevice applications such as energy harvesting systems,organic light-emitting diodes, photosensitizers, low-threshold lasers, and quantum logic elements, etc. A recent development in this area has been the construction of dendrimers specifically designed to exhibit novel forms of optical nonlinearity, exploiting the unique properties of these materials at high levels of photon flux. Starting from a thorough treatment of the underlying theory based on the principles of molecular quantum electrodynamics, it is possible to identify and characterize several optically nonlinear mechanisms for directed energy transfer and energy pooling in multichromophore dendrimers. Such mechanisms fall into two classes: first, those where two-photon absorption by individual donors is followed by transfer of the net energy to an acceptor; second, those where the excitation of two electronically distinct but neighboring donor groups is followed by a collective migration of their energy to a suitable acceptor. Each transfer process is subject to minor dissipative losses. In this paper we describe in detail the balance of factors and the constraints that determines the favored mechanism, which include the excitation statistics, structure of the energy levels, laser coherence factors, chromophore selection rules and architecture, possibilities for the formation of delocalized excitons, spectral overlap, and the overall distribution of donors and acceptors. Furthermore, it transpires that quantum interference between different mechanisms can play an important role. Thus, as the relative importance of each mechanism determines the relevant nanophotonic characteristics, the results reported here afford the means for optimizing highly efficient light-harvesting dendrimer devices

Not So Hip - The Expanded Burdens on and Consequences to Law Firms as Business Associates under Hitech Modifications to HIPAA

The Health Insurance Portability and Accountability Act of 1996 ( HIPAA ) governs the management of protected health information by covered entities (e.g., health care providers) and their business associates. However, the Health Information Technology for Economic and Clinical Health Act ( HITECH ), contained within the American Recovery and Reinvestment Act of 2009 ( ARRA ), drastically alters the scope of HIPAA regulations with regard to business associates, including law firms that routinely handle the protected health information ( PHI ) governed by HIPAA. Under the HITECH Act, the definition of business associate is expanded, and these entities are treated as covered for purposes of the HIPAA security regulations; this increased regulatory burden has important implications for the management of PHI at law firms and the practice of health care law as a whole. This article details the development of the HIPAA privacy and security regulations applicable to covered entities and business associates in the wake of the HITECH Act, with a focus on the updated regulatory scheme and its impact on law firms, especially those that deal with substantial amounts of PHI in the ordinary course of business. Beyond the development and content of the current HIPAA regulations that impact law firms, this piece addresses the practice implications of these regulations and proposes recommendations for costeffective and careful handling of PHI from the perspective of business associates and regulators alike

Not So Hip - The Expanded Burdens on and Consequences to Law Firms as Business Associates under Hitech Modifications to HIPAA

The Health Insurance Portability and Accountability Act of 1996 ( HIPAA ) governs the management of protected health information by covered entities (e.g., health care providers) and their business associates. However, the Health Information Technology for Economic and Clinical Health Act ( HITECH ), contained within the American Recovery and Reinvestment Act of 2009 ( ARRA ), drastically alters the scope of HIPAA regulations with regard to business associates, including law firms that routinely handle the protected health information ( PHI ) governed by HIPAA. Under the HITECH Act, the definition of business associate is expanded, and these entities are treated as covered for purposes of the HIPAA security regulations; this increased regulatory burden has important implications for the management of PHI at law firms and the practice of health care law as a whole. This article details the development of the HIPAA privacy and security regulations applicable to covered entities and business associates in the wake of the HITECH Act, with a focus on the updated regulatory scheme and its impact on law firms, especially those that deal with substantial amounts of PHI in the ordinary course of business. Beyond the development and content of the current HIPAA regulations that impact law firms, this piece addresses the practice implications of these regulations and proposes recommendations for costeffective and careful handling of PHI from the perspective of business associates and regulators alike