Classical theory of radiating strings

The divergent part of the self force of a radiating string coupled to gravity, an antisymmetric tensor and a dilaton in four dimensions are calculated to first order in classical perturbation theory. While this divergence can be absorbed into a renormalization of the string tension, demanding that both it and the divergence in the energy momentum tensor vanish forces the string to have the couplings of compactified N = 1 D = 10 supergravity. In effect, supersymmetry cures the classical infinities

Quantum tunneling of superconducting string currents

We investigate the decay of current on a superconducting cosmic string through quantum tunneling. We construct the instanton describing tunneling in a simple bosonic string model, and estimate the decay rate. The tunneling rate vanishes in the limit of a chiral current. This conclusion, which is supported by a symmetry argument, is expected to apply in general. It has important implications for the stability of chiral vortons.Comment: 16 pages, 2 figure

Practices of Rural Egyptian Birth Attendants During the Antenatal, Intrapartum and Early Neonatal Periods

Neonatal deaths account for almost two-thirds of infant mortality worldwide; most deaths are preventable. Two-thirds of neonatal deaths occur during the first week of life, usually at home. While previous Egyptian studies have identified provider practices contributing to maternal mortality, none has focused on neonatal care. A survey of reported practices of birth attendants was administered. Chi-square tests were used for measuring the statistical significance of inter-regional differences. In total, 217 recently-delivered mothers in rural areas of three governorates were interviewed about antenatal, intrapartum and postnatal care they received. This study identified antenatal advice of birth attendants to mothers about neonatal care and routine intrapartum and postpartum practices. While mothers usually received antenatal care from physicians, traditional birth attendants (dayas) conducted most deliveries. Advice was rare, except for breastfeeding. Routine practices included hand-washing by attendants, sterile cord-cutting, prompt wrapping of newborns, and postnatal home visits. Suboptimal practices included lack of disinfection of delivery instruments, unhygienic cord care, lack of weighing of newborns, and lack of administration of eye prophylaxis or vitamin K. One-third of complicated deliveries occurred at home, commonly attended by relatives, and the umbilical cord was frequently pulled to hasten delivery of the placenta. In facilities, mothers reported frequent use of forceps, and asphyxiated neonates were often hung upside-down during resuscitation. Consequently, high rates of birth injuries were reported. Priority areas for behaviour change and future research to improve neonatal health outcomes were identified, specific to type of provider (physician, nurse, or daya) and regional variations in practices

S1×S2S^1 \times S^2 wormholes and topological charge

I investigate solutions to the Euclidean Einstein-matter field equations with topology $S^1 \times S^2 \times R$ in a theory with a massless periodic scalar field and electromagnetism. These solutions carry winding number of the periodic scalar as well as magnetic flux. They induce violations of a quasi-topological conservation law which conserves the product of magnetic flux and winding number on the background spacetime. I extend these solutions to a model with stable loops of superconducting cosmic string, and interpret them as contributing to the decay of such loops.Comment: 18 pages (includes 6 figs.), harvmac and epsf, CU-TP-62

Psychometric Evaluation of the Transgender Congruence Scale

Introduction Despite increased attention to transgender and gender diverse (TGD) issues in psychological literature during the past decade, gaps remain for psychometric validation of TGD-specific measures. Kozee et al. (Psychology of Women Quarterly 36(2):179–196, 2012) addressed such gaps by creating the Transgender Congruence Scale (TCS), measuring gender acceptance and feelings of gender congruence between internal and external attributes across a broad range of gender identities. The current study extended Kozee and colleagues’ work by further examining the psychometric properties of the TCS. Methods Between October and November of 2017, 210 transmasculine, transfeminine, and gender diverse adults between ages 19 and 73 completed online surveys containing demographic, gender identity-specific, and well-being measures including the TCS. Results Results of confirmatory factor analysis replicated the original two-factor model (Appearance Congruence and Gender Identity Acceptance), with the elimination of two poorly loading items, resulting in a 10-item reduced model (TCS-10). Higher scores on TCS-10 were associated with positive scores on gender-related well-being, congruence, and pride, positive affect, and life satisfaction, as well as lower scores on gender-related dysphoria, non-affirmation, internalized transphobia, and marginalization. There were modest but significant associations between Gender Identity Congruence and both depression and negative affect. Conclusions Despite limitations of sample size and diversity of identities, the study reaffirmed the utility of the TCS as an overall construct of gender identity congruence with a 10-item reduced structure related to other established TGD constructs. Policy Implications Though socio-political climate is the ultimate domain for alleviating TGD stigma and discrimination, factors such as gender congruence are essential areas of focus to foster resiliency

Interaction between vortices in models with two order parameters

The interaction energy and force between widely separated strings is analyzed in a field theory having applications to superconducting cosmic strings, the SO(5) model of high-temperature superconductivity, and solitons in nonlinear optics. The field theory has two order parameters, one of which is broken in the vacuum (giving rise to strings), the other of which is unbroken in the vacuum but which could nonetheless be broken in the core of the string. If this does occur, there is an effect on the energetics of widely separated strings. This effect is important if the length scale of this second order parameter is longer than that of the other fields in the problem.Comment: 11 pages, 3 figures. Minor changes in the text. Accepted for publication in Phys. Rev.

Phases of dual superconductivity and confinement in softly broken N=2 supersymmetric Yang-Mills theories

We study the electric flux tubes that undertake color confinement in N=2 supersymmetric Yang-Mills theories softly broken down to N=1 by perturbing with the first two Casimir operators. The relevant Abelian Higgs model is not the standard one due to the presence of an off-diagonal coupling among different magnetic U(1) factors. We perform a preliminary study of this model at a qualitative level. BPS vortices are explicitely obtained for particular values of the soft breaking parameters. Generically however, even in the ultrastrong scaling limit, vortices are not critical but live in a "hybrid" type II phase. Also, ratios among string tensions are seen to follow no simple pattern. We examine the situation at the half Higgsed vacua and find evidence for solutions with the behaviour of superconducting strings. In some cases they are solutions to BPS equations.Comment: 15 pages, 1 figure, revtex; v2: typos corrected, final versio