Exact Soliton-like Solutions of the Radial Gross-Pitaevskii Equation

We construct exact ring soliton-like solutions of the cylindrically symmetric (i.e., radial) Gross- Pitaevskii equation with a potential, using the similarity transformation method. Depending on the choice of the allowed free functions, the solutions can take the form of stationary dark or bright rings whose time dependence is in the phase dynamics only, or oscillating and bouncing solutions, related to the second Painlev\'e transcendent. In each case the potential can be chosen to be time-independent.Comment: 8 pages, 7 figures. Version 2: stability analysis of the dark solutio

Evaluating elbow osteoarthritis within the prehistoric Tiwanaku state using generalized estimating equations (GEE).

OBJECTIVES:Studies of osteoarthritis (OA) in human skeletal remains can come with scalar problems. If OA measurement is noted as present or absent in one joint, like the elbow, results may not identify specific articular pathology data and the sample size may be insufficient to address research questions. If calculated on a per data point basis (i.e., each articular surface within a joint), results may prove too data heavy to comprehensively understand arthritic changes, or one individual with multiple positive scores may skew results and violate the data independence required for statistical tests. The objective of this article is to show that the statistical methodology Generalized Estimating Equations (GEE) can solve scalar issues in bioarchaeological studies. MATERIALS AND METHODS:Using GEE, a population-averaged statistical model, 1,195 adults from the core and one colony of the prehistoric Tiwanaku state (AD 500-1,100) were evaluated bilaterally for OA on the seven articular surfaces of the elbow joint. RESULTS:GEE linked the articular surfaces within each individual specimen, permitting the largest possible unbiased dataset, and showed significant differences between core and colony Tiwanaku peoples in the overall elbow joint, while also pinpointing specific articular surfaces with OA. Data groupings by sex and age at death also demonstrated significant variation. A pattern of elbow rotation noted for core Tiwanaku people may indicate a specific pattern of movement. DISCUSSION:GEE is effective and should be encouraged in bioarchaeological studies as a way to address scalar issues and to retain all pathology information

Angular position of nodes in the superconducting gap of YBCO

The thermal conductivity of a YBCO single crystal has been studied as a function of the relative orientation of the crystal axes and a magnetic field rotating in the Cu-O planes. Measurements were carried out at several temperatures below T_c and at a fixed field of 30 kOe. A four-fold symmetry characteristic of a superconducting gap with nodes at odd multiples of 45 degrees in k-space was resolved. Experiments were performed to exclude a possible macroscopic origin for such a four-fold symmetry such as sample shape or anisotropic pinning. Our results impose an upper limit of 10% on the weight of the s-wave component of the essentially d-wave superconducting order parameter of YBCO.Comment: 10 pages, 4 figure

Parental Anxiety Associated with Summer Camp Experiences: A Comparative Analysis Across Volunteer and Employee-Staffed Camps

Parent anxiety can limit a parent’s willingness to involve their child in out-of-school time experiences such as summer camps. Researchers have studied anxiety within the context of camp, but these studies used narrow frameworks of anxiety. In this exploratory study, we collected open-ended responses about causes of parent anxiety associated with summer camp experiences from 656 parents whose children attended one of two Extension-administered camps. The camps represented different camp staffing models—one primarily staffed by volunteers and the other primarily staffed by employees. The primary purpose of the study was to identify salient categories of anxiety and to examine if anxiety differed based on staffing model. The secondary purpose was to develop a camp-related parent anxiety measure informed by the anxiety categories. Eleven categories were constructed from the data, which both affirmed and expanded existing literature on parent anxiety associated with camp experiences. No differences in parent anxiety were found based on staffing model, suggesting that parents were no more likely to perceive anxiety associated with camp when the program was staffed with volunteers as they were when the program was staffed by employees. Implications for practice and future directions are examined

Dense Quark Matter Conductivity in Ultra-Intense Magnetic Field

Heavy-ion collisions generate a huge magnetic field of the order of $10^{18} G$ for the duration of about 0.2 fm/c. This time may become an order of magnitude longer if the electrical conductivity of quark matter is large. We calculate the conductivity in the regime of high density and show that contrary to naive expectations it only weakly depends on the MF.Comment: 3 pages, 0 figure

Onset of dielectric modes at 110K and 60K due to local lattice distortions in non-superconducting YBa_{2}Cu_{3}O_{6.0} crystals

We report the observation of two dielectric transitions at 110K and 60K in the microwave response of non-superconducting YBa_{2}Cu_{3}O_{6.0} crystals. The transitions are characterized by a change in polarizability and presence of loss peaks, associated with overdamped dielectric modes. An explanation is presented in terms of changes in polarizability of the apical O atoms in the Ba-O layer, affected by lattice softening at 110K, due to change in buckling of the Cu-O layer. The onset of another mode at 60K strongly suggests an additional local lattice change at this temperature. Thus microwave dielectric measurements are sensitive indicators of lattice softening which may be relevant to superconductivity.Comment: 5 pages, 3 ps format figure

Faking like a woman? Towards an interpretative theorization of sexual pleasure.

This article explores the possibility of developing a feminist approach to gendered and sexual embodiment which is rooted in the pragmatist/interactionist tradition derived from G.H. Mead, but which in turn develops this perspective by inflecting it through more recent feminist thinking. In so doing we seek to rebalance some of the rather abstract work on gender and embodiment by focusing on an instance of 'heterosexual' everyday/night life - the production of the female orgasm. Through engaging with feminist and interactionist work, we develop an approach to embodied sexual pleasure that emphasizes the sociality of sexual practices and of reflexive sexual selves. We argue that sexual practices and experiences must be understood in social context, taking account of the situatedness of sex as well as wider socio-cultural processes the production of sexual desire and sexual pleasure (or their non-production) always entails interpretive, interactional processes

Preparing the Next Generation of Science Teacher Educators: A Model for Developing PCK for Teaching Science Teachers

DOI:10.1007/s10972-008-9115-6 http://www.springerlink.com/content/a1j4p781335r2548/fulltext.pdfScience education doctoral programs often fail to address a critical piece—the explicit attention to the preparation of future science teacher educators. In this article, we argue that, in addition to developing skills and a knowledge base for research, doctoral students must be given the opportunity to observe, practice, and reflect on the pedagogical knowledge necessary to instruct science teachers. In particular, we contend that the construct of pedagogical content knowledge (PCK) can be adapted to the context of knowledge for teaching science teachers. We use the PCK construct to propose a model for the development of knowledge for teaching science teachers, grounded in our experiences as doctoral students and faculty mentors. We end by recommending a vision for doctoral preparation and a new standard to be included in the ASTE Professional Knowledge Standards for Science Teacher Educators

Methods or Madness: Preparing the Next Generation of Elementary Science Teacher Educators

This conference paper was presented at the Association for Science Teacher Education in Clearwater, FL in January 2007. Contains graphs and policy guidelines.In recent surveys of doctoral students in all fields (Fagen & Niebur, 2000; Nyquist & Woodford, 2000), respondents shared concerns that an overemphasis on research led to inadequate preparation for teaching, curricular planning, collegiality, and service. In one study (Davis & Fiske, 1999), 50% of respondents felt they received inadequate preparation as teaching assistants, and 59% felt that faculty in their programs did not emphasize the importance of teaching. A 2001 survey (Golde & Dore) indicated that most current doctoral students are primarily interested in becoming faculty members, even though most will not begin their careers in the types of institutions where they received their doctoral training. We often use such evidence to criticize our colleagues in the sciences about the inadequacies of their doctoral programs in preparing the next generation of university science instructors. However, what happens when we look inward to examine doctoral programs in science education