Non-minimal Gauge Mediation and Moduli Stabilization

In this paper we consider U(1)-gauged Polony'i model with two spurions coupled to a twisted closed string modulus. This offers a consistent setup for metastable SUSY breakdown which allows for moduli stabilization and naturally leads to gauge or hybrid gauge/gravitational mediation mechanism. Due to the presence of the second spurion one can arrange for a solution of the \mu and B_\mu problems in a version of modified Giudice-Masiero mechanism, which works both in the limit of pure gauge mediation and in the mixed regime of hybrid mediation.Comment: 12 pages, Discussion extended to include the effects of the gauge boson exchange. This should be version 2

Influence of substitution of the chromium ions by the nonmagnetic Sb and Al ions on the magnetization processes in CuCr2X4 (X = S, Se) spinels

Both the dc and ac magnetic susceptibilities as well as magnetization measurements were used to study the influence of the dilution of the magnetic chromium subarray by nonmagnetic antimony and aluminium ions on the magnetization processes for four spinel families under investigation. Substitution of the chromium ions by the nonmagnetic Sb and Al ions in the compounds under study leads to the very hard magnetization in the case of the compounds with Sb and very easy magnetization in the compounds with Al. This effect is connected with the electronic configurations of the Sb and Al ions as well as with ionic radii of these cations

On low-energy predictions of unification models inspired by F-theory

The aim of this paper is to discuss phenomenological consequences of a particular unification model (Z_3 model) inspired by F-theory. The most distinctive feature of this model is a variety of (cosmologically feasible) options for the NLSP and NNLSP, beyond the usually considered benchmark scenarios.Comment: LaTeX, 11 pages, 12 figure

Quark Spin and the Theta-Term for the QCD String

We describe a way in which spin of quarks can enter a consistent QCD string theory. We show that the spin factor of the 4d massless, spin 1/2 fermions is related to the self-intersection number of a 2d surfaces immersed in the 4d space. We argue that the latter quantity should appear in a consistent description of the QCD string. We also calculate the chiral anomaly and show that the self-intersection number corresponds to the topological charge $F{\tilde F}$ of QCD.Comment: 9 page

A Note on Anomalies in the AdS/CFT Correspondence

We test the AdS/CFT correspondence in the case of a d=4 N=2 SCFT by comparing chiral anomalies which are of order N in the 't Hooft large N limit. These include corrections of order 1/N to the conformal anomaly, thus testing the correspondence beyond the extreme large N limit. The field theory anomalies are reproduced by terms in the 7-brane effective action in the bulk.Comment: 13 pages, harvma

Factors affecting medical students in formulating their specialty preferences in Jordan

<p>Abstract</p> <p>Background</p> <p>In recent years there has been a growing appreciation of the issues of career preference in medicine as it may affect student learning and academic performance. However, no such studies have been undertaken in medical schools in Jordan. Therefore, we carried out this study to investigate the career preferences of medical students at Jordan University of Science and Technology and determine factors that might influence their career decisions.</p> <p>Methods</p> <p>A cross-sectional questionnaire-based survey was carried out among second, fourth and sixth year medical students at the Jordan University of Science and Technology, Irbid, Jordan during the academic year 2006/2007. A total of 440 students answered the questionnaire which covered demographic characteristics, specialty preferences, and the factors that influenced these career preferences. Possible influences were selected on the basis of a literature review and discussions with groups of medical students and physicians. Students were asked to consider 14 specialty options and select the most preferred career preference.</p> <p>Results</p> <p>The most preferred specialty expressed by male students was surgery, followed by internal medicine and orthopaedics, while the specialty most preferred by female students was obstetrics and gynaecology, followed by pediatrics and surgery. Students showed little interest in orthopedics, ophthalmology, and dermatology. While 3.1% of females expressed interest in anesthesiology, no male students did. Other specialties were less attractive to most students.</p> <p>Intellectual content of the specialty and the individual's competencies were the most influential on their preference of specialty. Other influential factors were the "reputation of the specialty", "anticipated income", and "focus on urgent care".</p> <p>Conclusion</p> <p>Surgery, internal medicine, pediatrics, and obstetrics and gynaecology were the most preferred specialty preferences of medical students at Jordan University of Science and Technology.</p

Kondo flow invariants, twisted K-theory and Ramond-Ramond charges

We take a worldsheet point of view on the relation between Ramond-Ramond charges, invariants of boundary renormalization group flows and K-theory. In compact super Wess-Zumino-Witten models, we show how to associate invariants of the generalized Kondo renormalization group flows to a given supersymmetric boundary state. The procedure involved is reminiscent of the way one can probe the Ramond-Ramond charge carried by a D-brane in conformal field theory, and the set of these invariants is isomorphic to the twisted K-theory of the Lie group. We construct various supersymmetric boundary states, and we compute the charges of the corresponding D-branes, disproving two conjectures on this subject. We find a complete agreement between our algebraic charges and the geometry of the D-branes.Comment: 58 pages. V4 : Problem with the bibliography correcte