Generalized iterated wreath products of cyclic groups and rooted trees correspondence

Consider the generalized iterated wreath product $\mathbb{Z}_{r_1}\wr \mathbb{Z}_{r_2}\wr \ldots \wr \mathbb{Z}_{r_k}$ where $r_i \in \mathbb{N}$. We prove that the irreducible representations for this class of groups are indexed by a certain type of rooted trees. This provides a Bratteli diagram for the generalized iterated wreath product, a simple recursion formula for the number of irreducible representations, and a strategy to calculate the dimension of each irreducible representation. We calculate explicitly fast Fourier transforms (FFT) for this class of groups, giving literature's fastest FFT upper bound estimate.Comment: 15 pages, to appear in Advances in the Mathematical Science

Naturopathy as a model of prevention-oriented, patient-centered primary care: A disruptive innovation in health care

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Background and Objective: The concept of a “disruptive innovation,” recently extended to health care, refers to an emerging technology that represents a new market force combined with a new value system, that eventually displaces some, or all, of the current leading “stakeholders, products and strategic alliances.” Naturopathy is a distinct system of traditional and complementary medicine recognized by theWorld Health Organization (WHO), emerging as a model of primary care. The objective here is to describe Naturopathy in the context of the criteria for a disruptive innovation. Methods: An evidence synthesis was conducted to evaluate Naturopathy as a potentially disruptive technology according to the defining criteria established by leading economists and health technology experts: (1) The innovation must cure disease; (2) must transform the way medicine is practiced; or (3) have an impact that could be disruptive or sustaining, depending on how it is integrated into the current healthcare marketplace. Results: The fact that Naturopathy de-emphasizes prescription drug and surgical interventions in favor of nonpharmacological health promotion and self-care could disrupt the present economic model that fuels health care costs. The patient-centered orientation of Naturopathy, combined with an emphasis on preventive behaviors and popular complementary and integrative health services like natural products, mind and body therapies, and other therapies not widely represented in current primary care models increase the likelihood for disruption. Conclusions: Because of its patient-centered approach and emphasis on prevention, naturopathy may disrupt or remain a durable presence in healthcare delivery depending on policymaker decisions

Simulations of the effects of tin composition gradients on the superconducting properties of Nb3Sn conductors

In powder-in-tube (PIT) Nb3Sn composites, the A15 phase forms between a central tin-rich core and a coaxial Nb tube, thus causing the tin content and superconducting properties to vary with radius across the A15 layer. Since this geometry is also ideal for magnetic characterization of the superconducting properties with the field parallel to the tube axis, a system of concentric shells with varying tin content was used to simulate the superconducting properties, the overall severity of the Sn composition gradient being defined by an index N. Using well-known scaling relationships and property trends developed in an earlier experimental study, the critical current density for each shell was calculated, and from this the magnetic moment of each shell was found. By summing these moments, experimentally measured properties such as pinning-force curves and Kramer plots could be simulated. We found that different tin profiles have only a minor effect on the shape of Kramer plots, but a pronounced effect on the irreversibility fields defined by the extrapolation of Kramer plots. In fact, these extrapolated values H_K are very close to a weighted average of the superconducting properties across the layer for all N. The difference between H_K and the upper critical field commonly seen in experiments is a direct consequence of the different ways measurements probe the simulated Sn gradients. Sn gradients were found to be significantly deleterious to the critical current density Jc, since reductions to both the elementary pinning force and the flux pinning scaling field H_K compound the reduction in Jc. The simulations show that significant gains in Jc of Nb3Sn strands might be realized by circumventing strong compositional gradients of tin.Comment: 10 pages, 8 figures, 2 tables, submitted to J. Appl. Phy

Generalized iterated wreath products of symmetric groups and generalized rooted trees correspondence

Consider the generalized iterated wreath product $S_{r_1}\wr \ldots \wr S_{r_k}$ of symmetric groups. We give a complete description of the traversal for the generalized iterated wreath product. We also prove an existence of a bijection between the equivalence classes of ordinary irreducible representations of the generalized iterated wreath product and orbits of labels on certain rooted trees. We find a recursion for the number of these labels and the degrees of irreducible representations of the generalized iterated wreath product. Finally, we give rough upper bound estimates for fast Fourier transforms.Comment: 18 pages, to appear in Advances in the Mathematical Sciences. arXiv admin note: text overlap with arXiv:1409.060

An algorithm for LET-analysis

An algorithm for the derivation of LET-distributions from pulse- height spectra obtained with proportional counters is described. The method is based on Fourier transformation: it is applicable to spherical as well as non-spherical proportional counters. The relation between the energy mean, LD, of LET and the energy mean, yD, of the lineal energy density is given

Fish-Derived Omega-3 Fatty Acids and Prostate Cancer: A Systematic Review.

BACKGROUND: The use of natural health products in prostate cancer (PrCa) is high despite a lack of evidence with respect to safety and efficacy. Fish-derived omega-3 fatty acids possess anti-inflammatory effects and preclinical data suggest a protective effect on PrCa incidence and progression; however, human studies have yielded conflicting results. METHODS: A search of OVID MEDLINE, Pre-MEDLINE, Embase, and the Allied and Complementary Medicine Database (AMED) was completed for human interventional or observational data assessing the safety and efficacy of fish-derived omega-3 fatty acids in the incidence and progression of PrCa. RESULTS: Of 1776 citations screened, 54 publications reporting on 44 studies were included for review and analysis: 4 reports of 3 randomized controlled trials, 1 nonrandomized clinical trial, 20 reports of 14 cohort studies, 26 reports of 23 case-control studies, and 3 case-cohort studies. The interventional studies using fish oil supplements in patients with PrCa showed no impact on prostate-specific antigen levels; however, 2 studies showed a decrease in inflammatory or other cancer markers. A small number of mild adverse events were reported and interactions with other interventions were not assessed. Cohort and case-control studies assessing the relationship between dietary fish intake and the risk of PrCa were equivocal. Cohort studies assessing the risk of PrCa mortality suggested an association between higher intake of fish and decreased risk of prostate cancer-related death. CONCLUSIONS: Current evidence is insufficient to suggest a relationship between fish-derived omega-3 fatty acid and risk of PrCa. An association between higher omega-3 intake and decreased PrCa mortality may be present but more research is needed. More intervention trials or observational studies with precisely measured exposure are needed to assess the impact of fish oil supplements and dietary fish-derived omega-3 fatty acid intake on safety, PrCa incidence, treatment, and progression

Fermi Surface of Alpha-Uranium at Ambient Pressure

We have performed de Haas-van Alphen measurements of the Fermi surface of alpha-uranium single crystals at ambient pressure within the alpha-3 charge density wave (CDW) state from 0.020 K - 10 K and magnetic fields to 35 T using torque magnetometry. The angular dependence of the resulting frequencies is described. Effective masses were measured and the Dingle temperature was determined to be 0.74 K +/- 0.04 K. The observation of quantum oscillations within the alpha-3 CDW state gives new insight into the effect of the charge density waves on the Fermi surface. In addition we observed no signature of superconductivity in either transport or magnetization down to 0.020 K indicating the possibility of a pressure-induced quantum critical point that separates the superconducting dome from the normal CDW phase.Comment: 11 pages, 4 figures, 3 table