Black Holes at the LHC

If the scale of quantum gravity is near a TeV, the LHC will be producing one black hole (BH) about every second. The BH decays into prompt, hard photons and charged leptons is a clean signature with low background. The absence of significant missing energy allows the reconstruction of the mass of the decaying BH. The correlation between the BH mass and its temperature, deduced from the energy spectrum of the decay products, can test experimentally the higher dimensional Hawking evaporation law. It can also determine the number of large new dimensions and the scale of quantum gravity.Comment: 5 pages, 3 figures, submitted to PRL. Results presented at the Les Houches Workshop "Physics at the TeV Colliders" (May 30, 2001) and the "Avatars of M-Theory" conference, ITP at Santa Barbara (June 7, 2001), http://online.itp.ucsb.edu/online/mtheory_c01/dimopoulo

Using Intervention Mapping to Develop an Efficacious Multicomponent Systems-Based Intervention to Increase Human Papillomavirus (HPV) Vaccination in a Large Urban Pediatric Clinic Network

Background: The CDC recommends HPV vaccine for all adolescents to prevent cervical, anal, oropharyngeal, vaginal, vulvar, and penile cancers, and genital warts. HPV vaccine rates currently fall short of national vaccination goals. Despite evidence-based strategies with demonstrated efficacy to increase HPV vaccination rates, adoption and implementation of these strategies within clinics is lacking. The Adolescent Vaccination Program (AVP) is a multicomponent systems-based intervention designed to implement five evidence-based strategies within primary care pediatric practices. The AVP has demonstrated efficacy in increasing HPV vaccine initiation and completion among adolescents 10-17 years of age. The purpose of this paper is to describe the application of Intervention Mapping (IM) toward the development, implementation, and formative evaluation of the clinic-based AVP prototype. Methods: Intervention Mapping (IM) guided the development of the Adolescent Vaccination Program (AVP). Deliverables comprised: a logic model of the problem (IM Step 1); matrices of behavior change objectives (IM Step 2); a program planning document comprising scope, sequence, theory-based methods, and practical strategies (IM Step 3); functional AVP component prototypes (IM Step 4); and plans for implementation (IM Step 5) and evaluation (IM Step 6). Results: The AVP consists of six evidence-based strategies implemented in a successful sequenced roll-out that (1) established immunization champions in each clinic, (2) disseminated provider assessment and feedback reports with data-informed vaccination goals, (3) provided continued medical and nursing education (with ethics credit) on HPV, HPV vaccination, message bundling, and responding to parent hesitancy, (4) electronic health record cues to providers on patient eligibility, and (5) patient reminders for HPV vaccine initiation and completion. Conclusions: IM provided a logical and systematic approach to developing and evaluating a multicomponent systems-based intervention to increase HPV vaccination rates among adolescents in pediatric clinics

Electric Field-induced Charge Transport in Redox-active Molecular Junctions

The formation of well-defined three-dimensional (3D) redox-active molecular nanostructures at the electrode surfaces may open additional routes to achieve higher conductance in molecular junctions (MJs). We report here experimental and theoretical charge transport analysis on electroactive ruthenium(II)-tri(phenanthroline) [Ru(Phen)3]-based molecular junctions covalently grown on patterned ITO electrode. Thicknesses of the molecular layers are varied between 4 to 13 nm, thanks to the potential-driven electrochemical technique to achieve it. A thin layer of Al was deposited on top contact over ITO/ Ru(Phen)3 to fabricate large-area solid-state molecular junctions with a stacking configuration of ITO/[Ru(Phen)3]4nm, 10nm, 13nm/Al. The electrified molecular junctions show LUMO-mediated electron-driven resonant charge conduction with attenuation in conductance as a function of the length of Ru(Phen)3 layers (\b{eta} = 0.48 to 0.60 nm-1). Molecular junctions consisting of 4 nm Ru(Phen)3 layers follow quantum tunneling, while the thicker junctions (10, and 13 nm) follow Poole-Frenkel and electric-field induced charge conduction. Considering the energy level of frontier molecular orbitals, Fermi energy of ITO, and Al contact, a mechanism of symmetric current-voltage features with respect to the bias-polarity is predicted. The present work describes a simple, controllable, low-cost, and versatile approach to fabricating 3D molecular assembly for mimicking conventional electronic functions.Comment: 13 pages, 5 Figure

Hematogenous infantile infection presenting as osteomyelitis and septic arthritis: a case report

The case of a 6-month old male infant presenting at the emergency department with fever and swelling at the left knee joint is discussed. Laboratory tests showed an inflammatory condition. Left knee plain radiograph demonstrated local soft tissue oedema. Percutaneous needle aspiration of articular fluid showed a positive culture for Staphylococcus aureus. The diagnosis of septic arthritis was confirmed. Because of inadequate response to treatment an MRI study was followed to evaluate possible abscesses. The presence of an abscess in the suprapatellar bursa was confirmed and an additional inflammatory process of the bone marrow was revealed, consistent with osteomyelitis. The pathophysiology, the imaging findings, the patient’s management and a review of septic arthritis and osteomyelitis coexistence are presented in this paper

Stabilization of Sub-Millimeter Dimensions: The New Guise of the Hierarchy Problem

A new framework for solving the hierarchy problem was recently proposed which does not rely on low energy supersymmetry or technicolor. The fundamental Planck mass is at a \tev and the observed weakness of gravity at long distances is due the existence of new sub-millimeter spatial dimensions. In this picture the standard model fields are localized to a $(3+1)$-dimensional wall or ``3-brane''. The hierarchy problem becomes isomorphic to the problem of the largeness of the extra dimensions. This is in turn inextricably linked to the cosmological constant problem, suggesting the possibility of a common solution. The radii of the extra dimensions must be prevented from both expanding to too great a size, and collapsing to the fundamental Planck length \tev^{-1}. In this paper we propose a number of mechanisms addressing this question. We argue that a positive bulk cosmological constant $\bar\Lambda$ can stabilize the internal manifold against expansion, and that the value of $\bar\Lambda$ is not unstable to radiative corrections provided that the supersymmetries of string theory are broken by dynamics on our 3-brane. We further argue that the extra dimensions can be stabilized against collapse in a phenomenologically successful way by either of two methods: 1) Large, topologically conserved quantum numbers associated with higher-form bulk U(1) gauge fields, such as the naturally occurring Ramond-Ramond gauge fields, or the winding number of bulk scalar fields. 2) The brane-lattice-crystallization of a large number of 3-branes in the bulk. These mechanisms are consistent with theoretical, laboratory, and cosmological considerations such as the absence of large time variations in Newton's constant during and after primordial nucleosynthesis, and millimeter-scale tests of gravity.Comment: Corrected referencing to important earlier work by Sundrum, errors fixed, additional discussion on radion phenomenology, conclusions unchanged, 23 pages, LaTe

Implications of Low Energy Supersymmetry Breaking at the Tevatron

The signatures for low energy supersymmetry breaking at the Tevatron are investigated. It is natural that the lightest standard model superpartner is an electroweak neutralino, which decays to an essentially massless Goldstino and photon, possibly within the detector. In the simplest models of gauge-mediated supersymmetry breaking, the production of right-handed sleptons, neutralinos, and charginos leads to a pair of hard photons accompanied by leptons and/or jets with missing transverse energy. The relatively hard leptons and softer photons of the single e^+e^- \gamma \gamma + \EmissT event observed by CDF implies this event is best interpreted as arising from left-handed slepton pair production. In this case the rates for l^{\pm} \gamma \gamma + \EmissT and \gamma \gamma + \EmissT are comparable to that for l^+l^- \gamma \gamma + \EmissT.Comment: 18 pages, Latex, tables correcte

Neutrino Masses from Large Extra Dimensions

Recently it was proposed that the standard model (SM) degrees of freedom reside on a $(3+1)$-dimensional wall or ``3-brane'' embedded in a higher-dimensional spacetime. Furthermore, in this picture it is possible for the fundamental Planck mass \mst to be as small as the weak scale \mst\simeq O(\tev) and the observed weakness of gravity at long distances is due the existence of new sub-millimeter spatial dimensions. We show that in this picture it is natural to expect neutrino masses to occur in the 10^{-1} - 10^{-4}\ev range, despite the lack of any fundamental scale higher than \mst. Such suppressed neutrino masses are not the result of a see-saw, but have intrinsically higher-dimensional explanations. We explore two possibilities. The first mechanism identifies any massless bulk fermions as right-handed neutrinos. These give naturally small Dirac masses for the same reason that gravity is weak at long distances in this framework. The second mechanism takes advantage of the large {\it infrared} desert: the space in the extra dimensions. Here, small Majorana neutrino masses are generated by breaking lepton number on distant branes.Comment: 17 pages, late