Microcanonical Thermodynamics of First Order Phase Transitions studied in the Potts Model

Phase transitions of first and second order can easily be distinguished in small systems in the microcanonical ensemble. Configurations of phase coexistence, which are suppressed in the canonical formulation, carry important information about the main characteristics of first order phase transitions like the transition temperature, the latent heat, and the interphase surface tension. The characterisitc backbending of the micro- canonical caloric equation of state T(E) (not to be confused with the well known Van der Waals loops in ordinary thermodynamics) leading to a negative specific heat is intimatly linked to the interphase surface entropy.Comment: Latex, 4 eps-figures, graphicx.st

Mobile phones as a social medium for the deaf: a uses and gratifications study

New communications technologies include mobile phones that now provide access to the Internet and text messaging. The present study used the conceptual framework set forth by past uses and gratifications research and shifted focus to the media needs of one specific population: the deaf and hard-of-hearing. Past literature focused on the uses and gratifications of traditional media, but less is known about the consumption of new media by deaf people. Using a convenience sample of hearing and deaf students at RIT, findings from an e-mailed survey instrument showed deaf and hard-of-hearing students were more likely to use instant messaging and e-mail, whereas the voice function was used more by hearing students. Text messaging use was comparable between the two groups

Role of Scalar Meson Resonances in $K_{L}^{0} \rightarrow \pi^{0} \gamma \gamma Decay

Corrections to $K_{L}^{0}\rightarrow \pi^{0} \gamma \gamma$ decay induced by scalar meson exchange are studied within chiral perturbation theory. In spite of bad knowledge of scalar-mesons parameters, the calculated branching ratio can be changed by a few percent.Comment: 18 pages of text, 2 figures (available upon request); preprint IJS-TP-16-94 , TUM-T31-63-94

Vector meson decays from the Extended Chiral Quark Model

We derive the the effective lagrangian that describes the interactions among vector, axial-vector mesons and pseudoscalars starting from the extended chiral quark model (ECQM). The results for the low-energy constants of this effective lagrangian have a parametric resemblance with existing predictions based on the Nambu-Jona-Lasinio model (except for some overall signs that we correct), but are numerically different. Therefore a precise measurement of these decay constants can shed some light on the way chiral symmetry breaking is modelled in QCD. Although most of the constants are poorly measured, comparison with phenomenology allows us to determine one of the parameters of the ECQM that could not be fully determined in previous analyses.Comment: 7 pages, revtex

Long distance contribution to K+→π+ννˉK^+ \to \pi^+ \nu {\bar \nu} decay and O(p4)O(p^4) terms in CHPT

The long distance contribution to $K^+ \to \pi^+ \nu {\bar \nu}$ is calculated using chiral perturbation theory. The leading contribution comes from $O(p^4)$ tree terms. The branching ratio of the $O(p^4)$ long distance contribution is found to be of order $10_{-3}$ smaller than the short distance contributions.Comment: 12 pages, 1 figure (available upon request

Electronically Controllable Surgical Tools

The present disclosure relates to electrically controllable surgical tools. In general, surgical devices are provided having an electrically controllable, fingered operating end for use in angiography, endovascular and/or neurological surgery. The finger(s) at the operating end can be made from ionic polymer metal composite (IPMC) material to facilitate control of the finger(s)

Electrically Controllable Surgical Tools

The present disclosure relates to electrically controllable surgical tools. In general, surgical devices are provided having an electrically controllable, fingered operating end for use in angiography, endovascular and/or neurological surgery. The finger(s) at the operating end can be made from ionic polymer metal composite (IPMC) material to facilitate control of the finger(s)

The Role of Underutilization of Protective Behavioral Strategies in the Relation of Social Anxiety with Risky Drinking

Social anxiety is prominent among undergraduates and increases the risk of experiencing alcohol problems. In fact, social anxiety more than quadruples the risk of developing an alcohol use disorder, yet it is inconsistently related to heavier drinking. Inconsistent findings may be due to lack of attention on protective behavioral strategies (PBS) among socially anxious drinkers. PBS are cognitive-behavioral strategies to reduce drinking and alcohol-related harm. Due to the nature of social anxiety, affected individuals may be especially vulnerable to PBS underutilization, leading to heavier and more problematic drinking. The current study examined the mediating role of PBS in the relationships of social anxiety with past-month drinking and alcohol problems using cross-sectional data among current (past-month) heavy undergraduate drinkers (N = 431). Social anxiety was significantly positively related to past-month alcohol problems and peak drinking. Social anxiety was significantly negatively related to typical drinking, drinking frequency, and PBSS Manner of Drinking. Social anxiety was indirectly (via PBSS Manner of Drinking) related to greater past-month peak drinks and more drinking problems. Findings suggest that socially anxious persons may be vulnerable to heavier and more problematic drinking due to PBS underutilization. Treatment implications are discussed

Rare Kaon Decays in the 1/Nc1/N_c-Expansion

We study the unknown coupling constants that appear at order $p^4$ in the Chiral Perturbation Theory analysis of $K \to \pi \gamma^* \to \pi l^+ l^-$, $K^{+-} \to \pi^{+-} \gamma \gamma$ and $K \to \pi \pi \gamma$ decays. To that end, we compute the chiral realization of the $\Delta S \, = \, 1$ Hamiltonian in the framework of the $1/N_c$-expansion of the low-energy action. The phenomenological implications are also discussed.Comment: 18 pages, LaTeX, CPT-92/P.279

Radiative Kaon Decays K±→π±π0γK^\pm\to\pi^\pm\pi^0\gamma and Direct CP Violation

It is stressed that a measurement of the electric dipole amplitude for direct photon emission in \kpm decays through its interference with inner bremsstrahlung is important for differentiating among various models. Effects of amplitude CP violation in the radiative decays of the charged kaon are analyzed in the Standard Model in conjunction with the large $N_c$ approach. We point out that gluon and electromagnetic penguin contributions to the CP-violating asymmetry between the Dalitz plots of \kpm are of equal weight. The magnitude of CP asymmetry ranges from $2\times 10^{-6}$ to $1\times 10^{-5}$ when the photon energy in the kaon rest frame varies from 50 MeV to 170 MeV.Comment: Latex, 11 pages, ITP-SB-93-36, IP-ASTP-22-9