Pennsylvania Folklife Vol. 34, No. 2

• A Fiddler\u27s Life • An Interpretation of Some Ritual and Food Elements of the Brethren Love Feast • Pottery Making in Quakertown: 1800-1879 • Teddy Bears: An Enduring Folk Tradition • Lucia Day • Dippy, Son of Puddin\u27 • Persecution and Genocide: The General Problem as Illustrated by the Anabaptist Experiencehttps://digitalcommons.ursinus.edu/pafolklifemag/1106/thumbnail.jp

Critical Behaviour of Structure Factors at a Quantum Phase Transition

We review the theoretical behaviour of the total and one-particle structure factors at a quantum phase transition for temperature T=0. The predictions are compared with exact or numerical results for the transverse Ising model, the alternating Heisenberg chain, and the bilayer Heisenberg model. At the critical wavevector, the results are generally in accord with theoretical expectations. Away from the critical wavevector, however, different models display quite different behaviours for the one-particle residues and structure factors.Comment: 17 pp, 10 figure

Anabaptist Spirituality and the Heidelberg Catechism

Although the Anabaptists are not explicitly mentioned in the Heidelberg Catechism, it is generally acknowledged that the catechism influenced by the debates with the so-called radical reformation. This paper assesses Zacharias Ursinus’ Commentary on the Heidelberg Catechism and the report of the 1571 Frankenthal disputation in order to get a clearer picture of this influence. It concludes that the implicit polemics against the Anabaptists regard the relationship between the Old and the New Testaments and Christology. The spirituality of the Heidelberg Catechism stresses the continuity between creation and recreation, between ‘Paradise Lost’ and ‘Paradise Regained’. Over against the restitution of the church it advocates its reformation and instead of a new creation it expects the redemption of the fallen world from the power of sin and death

Biophysical interactions in tropical agroforestry systems

sequential systems, simultaneous systems Abstract. The rate and extent to which biophysical resources are captured and utilized by the components of an agroforestry system are determined by the nature and intensity of interac-tions between the components. The net effect of these interactions is often determined by the influence of the tree component on the other component(s) and/or on the overall system, and is expressed in terms of such quantifiable responses as soil fertility changes, microclimate modification, resource (water, nutrients, and light) availability and utilization, pest and disease incidence, and allelopathy. The paper reviews such manifestations of biophysical interactions in major simultaneous (e.g., hedgerow intercropping and trees on croplands) and sequential (e.g., planted tree fallows) agroforestry systems. In hedgerow intercropping (HI), the hedge/crop interactions are dominated by soil fertility improvement and competition for growth resources. Higher crop yields in HI than in sole cropping are noted mostly in inherently fertile soils in humid and subhumid tropics, and are caused by large fertility improvement relative to the effects of competition. But, yield increases are rare in semiarid tropics and infertile acid soils because fertility improvement does not offse