Search for Charged Higgs Bosons in e+e- Collisions at \sqrt{s} = 189 GeV

A search for pair-produced charged Higgs bosons is performed with the L3 detector at LEP using data collected at a centre-of-mass energy of 188.6 GeV, corresponding to an integrated luminosity of 176.4 pb^-1. Higgs decays into a charm and a strange quark or into a tau lepton and its associated neutrino are considered. The observed events are consistent with the expectations from Standard Model background processes. A lower limit of 65.5 GeV on the charged Higgs mass is derived at 95 % confidence level, independent of the decay branching ratio Br(H^{+/-} -> tau nu)

Enhanced magnetic properties in antiferromagnetic-core/ferrimagnetic-shell nanoparticles

Bi-magnetic core/shell nanoparticles are gaining increasing interest due to their foreseen applications. Inverse antiferromagnetic(AFM)/ferrimagnetic(FiM) core/shell nanoparticles are particularly appealing since they may overcome some of the limitations of conventional FiM/AFM systems. However, virtually no simulations exist on this type of morphology. Here we present systematic Metropolis Monte Carlo simulations of the exchange bias properties of such nanoparticles. The coercivity, H C, and loop shift, H ex, present a non-monotonic dependence with the core diameter and the shell thickness, in excellent agreement with the available experimental data. Additionally, we demonstrate novel unconventional behavior in FiM/AFM particles. Namely, while H C and H ex decrease upon increasing FiM thickness for small AFM cores (as expected), they show the opposite trend for large cores. This presents a counterintuitive FiM size dependence for large AFM cores that is attributed to the competition between core and shell contributions, which expands over a wider range of core diameters leading to non-vanishing H ex even for very large cores. Moreover, the results also hint different possible ways to enhance the experimental performance of inverse core/shell nanoparticles for diverse applications

Characterization of Sociodemographic and Clinicopathological Features in Brazilian Patients with Vulvar Squamous Cell Carcinoma

Aim: To investigate sociodemographic and clinical-epidemiological profiles of patients with vulvar carcinoma in Sao Paulo, the largest city of Brazil, to establish a more consistent profile of these features once the incidence of vulvar carcinoma has risen considerably. Data regarding the epidemiological aspects of this tumor are scarce. Methods: A retrospective study was performed using 300 medical records from patients diagnosed with squamous cell carcinoma of the vulva and surgically treated at A.C. Camargo Hospital in Sao Paulo, Brazil, from 1978 to 2009. Results: The median age of onset was 70 years, ranging from 15 to 98 years, and most women were white (88.51%). Most patients (83.54%) had little or no schooling and had the lowest survival curve. Many patients were diagnosed in the early stages of the disease (57.09% FIGO IB), 59% had complications due to surgery and 43.71% had disease recurrence, of which about 70% died. Conclusions: Our study adds 300 Brazilian cases of vulvar carcinoma to the world literature. Given the high rate of disease recurrence and mortality in Brazil, we conclude that regular gynecologic evaluation and educational policies should be reinforced in order to raise awareness for vulvar cancer. Copyright (c) 2012 S. Karger AG, Basel751536

Core/Shell Bimagnetic Nanoparticles

The advances in the physical and chemical fabrication methods have enabled the possibility to produce artificial nanostructures whose properties are different from that of their constituent materials. The presence of interfaces in core/shell bimagnetic nanoparticles introduces additional interactions that could radically modify the static and dynamic magnetic behavior of the systems. The number of parameters that governs the magnetic behavior grows enormously and the opportunity to manipulate, control, and understand the role played by each one of them, opens a wide range of possibilities to design novel materials with suited properties. The magnetic response changes depend on the magnetic ordering and anisotropy of the phases, the core size and shell thickness, the quality of the interface, and the strength of the interface exchange coupling. In this chapter, we discuss the new properties found in core/shell bimagnetic nanoparticles and analyze the main characteristics that have to be taken into account to design a system with a particular response.Fil: Winkler, Elin Lilian. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigación y Aplicaciones No Nucleares. Gerencia de Física. Laboratorio de Resonancias Magnéticas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro | Universidad Nacional de Cuyo. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro; ArgentinaFil: Zysler, Roberto Daniel. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigación y Aplicaciones No Nucleares. Gerencia de Física. Laboratorio de Resonancias Magnéticas; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; Argentin

Community Structure of Shallow Water Alcyonacea (Anthozoa: Octocorallia) from the Southern Tropical Eastern Pacific

Alcyonacea are sessile invertebrates, which can significantly shape the boundary layer in coral reefs and rocky habitats. Ecological aspects in this taxon have been well studied in the Caribbean, Mediterranean, and Indo-Pacific. With few recent exceptions, studies in the Eastern Pacific focused on taxonomy. We present a quantitative assessment of Alcyonacea communities from the southern Tropical Eastern Pacific, based on video transects in the Marine Reserve El Pelado. Seventeen species from the Plexauridae (8), Gorgoniidea (8), and Clavularidae (1) were identified, comprising 6963 colonies dominated by Muricea (86.7%), particularly M. plantaginea (48.6%). The overwhelming dominance of M. plantaginea was the most striking and previously unreported community trait, which contributed to a moderate Shannon entropy (n = 31, H mean 1.40, SD 0.22), equitability (n = 31, HE mean 0.16, SD 0.4), and species diversity expressed as effective number of species (n = 31, mean 4.16, SD 0.87). Few common species overprinted a more variable and subtle community pattern among rarer species, suggested in agglomerative hierarchical cluster analyses. Four species (M. plantaginea, M. purpurea, M. fruticosa and Leptogorgia alba) had the strongest influence on site groupings in the correspondence analysis between a principal component analysis of a Hellinger-transformed Alcyonacea species matrix and substrate categories, with filamentous turf algae and crustose coralline algae being the main determinants of site differentiation. Muricea plantaginea’s qualities of a keystone species, and the eurytopic and stenoecious distribution traits among some species are discussed. The invasive Carijoa riisei was confirmed as biological thereat to other Alcyonacea, and possible physiological distribution limitations are indicated