Instrumentation for Millimeter-wave Magnetoelectrodynamic Investigations of Low-Dimensional Conductors and Superconductors

We describe instrumentation for conducting high sensitivity millimeter-wave cavity perturbation measurements over a broad frequency range (40-200 GHz) and in the presence of strong magnetic fields (up to 33 tesla). A Millimeter-wave Vector Network Analyzer (MVNA) acts as a continuously tunable microwave source and phase sensitive detector (8-350 GHz), enabling simultaneous measurements of the complex cavity parameters (resonance frequency and Q-value) at a rapid repetition rate (approx. 10 kHz). We discuss the principal of operation of the MVNA and the construction of a probe for coupling the MVNA to various cylindrical resonator configurations which can easily be inserted into a high field magnet cryostat. We also present several experimental results which demonstrate the potential of the instrument for studies of low-dimensional conducting systems.Comment: 20 pages including fig

T-Parity Violation by Anomalies

Little Higgs theories often rely on an internal parity ("T-parity'') to suppress non-standard electroweak effects or to provide a dark matter candidate. We show that such a symmetry is generally broken by anomalies, as described by the Wess-Zumino-Witten term. We study a simple SU(3) x SU(3)/SU(3) Little Higgs scheme where we obtain a minimal form for the topological interactions of a single Higgs field. The results apply to more general models, including [SU(3) x SU(3)/SU(3)]^4, SU(5)/SO(5), and SU(6)/Sp(6).Comment: 17 page

Thinking about audience and agency in the museum: models from historical research

This paper examines a current trend within museum studies to conceptualise the contemporary museum as democratic, open, and working in partnership with its community, which is seen as a fundamental change from museums at some point in the past, when they were didactic and produced or encouraged a passive audience. This trend, it maintains, is not just produced by museums needing to fit into various agendas for social inclusivity, but also by some of the most important texts in museum history, which look at the ways in which various forms of agency worked to deny agency to the public. It argues that such a view radically understates the forms of agency available to ‘outsiders’ to museums in the past; and that as a corollary, analyses of the contemporary museum need to be wary of seeing shared agency as already achieved. By exploring the forces which work to distribute agency widely inside and beyond the museum, alongside those which worked to centralise agency in the institution of the museum and its curators, we can gain a much fuller understanding of museums past and present

Prototype Environmental Assessment of the impacts of siting and construction of an SPS ground receiving station

A prototype assessment of the environmental impacts of siting and constructing a Satellite Power System (SPS) Ground Receiving Station (GRS) is reported. The objectives of the study were: (1) to develop an assessment of the nonmicrowave related impacts of the reference system SPS GRS on the natural environment; (2) to assess the impacts of GRS construction and operations in the context of actual baseline data for a site in the California desert; and (3) to identify critical GRS characteristics or parameters that are most significant in terms of the natural environment

Making Upper Division Mathematics Courses Relevant for Pre-Service Teachers

This article addresses the disconnect that in-service and pre-service secondary school teachers feel between the material presented in upper division mathematics courses and high school classroom practice. Two examples are given from an abstract algebra course in which this problem is addressed

What Are the Odds that Everyone is Depraved?

Why does God allow evil? One hypothesis is that God desires the existence and activity of free creatures but He was unable to create a world with such creatures and such activity without also allowing evil. If Molinism is true, what probability should be assigned to this hypothesis? Some philosophers claim that a low probability should be assigned because there are an infinite number of possible people and because we have no reason to suppose that such creatures will choose one way rather than another. Arguments like this depend on the principle of indifference. But that principle is rejected by most philosophers of probability. Some philosophers claim that a low probability should be assigned because doing otherwise violates intuitions about freewill. But such arguments can be addressed through strategies commonly employed to defend theories with counterintuitive results across ethics and metaphysics

A holistic aboriginal framework for individual healing

This paper offers up an holistic Indigenous model of individual healing that utilizes medicine wheel teachings to break down the four aspects (spiritual, emotional, physical, and mental) of individual wellness. Teachings about each direction are presented followed by practice techniques for each aspect of the individual self. It is bookended by an introduction to the historical trauma faced by Indigenous peoples in Canada, and a conclusion that draws implications for healing

Reducing attrition in panel studies in developing countries.

BACKGROUND: Panel studies offer repeated observations of individuals over time, but the mobility of populations in the developing world often causes attrition in panel studies. Such attrition can cause bias if it is selective but can be reduced by tracking respondents. Tracking in developing countries can be costly and difficult as populations are often highly mobile, infrastructure is poor, structures frequently change, and formal address systems or population records rarely exist. Method In this paper, the attrition and tracking experiences of panel studies in developing countries are reviewed and recommendations made for ensuring effective tracking. Comments Tracking can reduce attrition by up to 45% and is feasible if procedures are locally appropriate, well planned, involve the community, collect as much locating data as possible, and have explicit criteria, and if tracking is done at regular intervals, and interviewers are well trained, supervised, and motivated. CONCLUSION: Attrition is an important issue in panel studies, whilst tracking can be costly it can reduce attrition if effective procedures are used