Simultaneous Contralateral Vestibular Schwannoma and Middle Ear Paraganglioma Tumor

To the best of our knowledge, only 2 cases of a simultaneous contralateral vestibular schwannoma (VS) and middle ear paraganglioma (MEP) have previously been reported in literature. We report the third case observed in a 43-year-old male, who presented with an 11-year history of right-sided hearing loss and a 1-year history of left-sided pulsatile tinnitus. A magnetic resonance imaging (MRI) showed a VS on the right side and computer tomography (CT) identified a Fisch type A1 paraganglioma on the left side. The VS was treated using a translabyrinthine approach and the MEP was kept under radiological observation for 1 year. Due to the growth of the MEP (Fisch type A2), it was treated with excision via a retroauricular approach. Our case was very challenging because there was a different and important pathology on each side, both carrying a risk of deafness as a consequence of the disease and/or the treatments

Rock properties of the upper-crust in Central Apennines (Italy) derived from high-resolution 3-D tomography

High-resolution 3-D P and S-wave velocity models of a central sector of the Apennines (Central Italy) are computed by inverting first arrival times from an aftershock sequence (September–December, 1997) following the Mw 5.7 and Mw 6.0 Umbria-Marche earthquakes that occurred on September 26, 1997. The high quality of the data set, especially for the S-wave, allows us to compute 3-D variations in Vp, Vp/Vs and Vp · Vs. The anomalies can be interpreted as lateral changes in rock type and fracturing, which control fluid diffusion and variation in pore pressure. This is in agreement with a poro-elastic view that can be inferred from the spatio-temporal evolution of the seismic sequence

Dark matter from the scalar sector of 3-3-1 models without exotic electric charges

We show that three SU(2) singlet neutral scalars (two CP-even and one CP-odd) in the spectrum of models based on the gauge symmetry SU(3)_c X SU(3)_L X U(1)_X, which do not contain exotic electric charges, are realistic candidates for thermally generated self-interacting dark matter in the Universe, a type of dark matter that has been recently proposed in order to overcome some difficulties of collisionless cold dark matter models at the galactic scale. These candidates arise without introducing a new mass scale in the model and/or without the need for a discrete symmetry to stabilize them, but at the expense of tuning several combinations of parameters of the scalar potential.Comment: RevTeX, 11 pages. v2: typos corrected, one reference added. v3: clarifications added, four more references added. To appear in Europhys. Let

Energy and variance optimization of many body wave functions

We present a simple, robust and efficient method for varying the parameters in a many-body wave function to optimize the expectation value of the energy. The effectiveness of the method is demonstrated by optimizing the parameters in flexible Jastrow factors, that include 3-body electron-electron-nucleus correlation terms, for the NO$_2$ and decapentaene (C$_{10}$H$_{12}$) molecules. The basic idea is to add terms to the straightforward expression for the Hessian that are zero when the integrals are performed exactly, but that cancel much of the statistical fluctuations for a finite Monte Carlo sample. The method is compared to what is currently the most popular method for optimizing many-body wave functions, namely minimization of the variance of the local energy. The most efficient wave function is obtained by optimizing a linear combination of the energy and the variance.Comment: 4 pages, 4 figures, minor corrections of inexact statements, missing

Local structure of REFeAsO (RE=La, Pr, Nd, Sm) oxypnictides studied by Fe K-edge EXAFS

Local structure of REOFeAs (RE=La, Pr, Nd, Sm) system has been studied as a function of chemical pressure varied due to different rare-earth size. Fe K-edge extended X-ray absorption fine structure (EXAFS) measurements in the fluorescence mode has permitted to compare systematically the inter-atomic distances and their mean square relative displacements (MSRD). We find that the Fe-As bond length and the corresponding MSRD hardly show any change, suggesting the strongly covalent nature of this bond, while the Fe-Fe and Fe-RE bond lengths decrease with decreasing rare earth size. The results provide important information on the atomic correlations that could have direct implication on the superconductivity and magnetism of REOFeAs system, with the chemical pressure being a key ingredient

Evidence of an advantage in visuo-spatial memory for bilingual compared to monolingual speakers

Previous research has indicated that bilinguals outperform monolinguals in cognitive tasks involving spatial working memory. The present study examines evidence for this claim using a different and arguably more ecologically valid method (the change blindness task). Bilingual and monolingual participants were presented with two versions of the same scenes and required to press a key as soon as they identified the alteration. They also completed the word and alpha span tasks, and the Corsi blocks task. The results in the change blindness task, controlled for group differences in non-verbal reasoning, indicated that bilinguals were faster and more accurate than monolinguals at detecting visual changes. Similar group differences were found on the Corsi block task. Unlike previous findings, no group differences were found on the verbal memory tasks. The results are discussed with reference to mechanisms of cognitive control as a locus of transfer between bilingualism and spatial working memory tasks

TOWARDS A SUSTAINABLE AND CONTEXT-BASED APPROACH TO ANTI-SEISMIC RETROFITTING TECHNIQUES FOR VERNACULAR ADOBE BUILDINGS IN COLOMBIA

Abstract. In Colombia earthen buildings, mostly adobe, makes up 80% of the national monumental heritage and historic urban centres. Moreover, vernacular earthen techniques have been largely used for dwellings in rural villages, small towns or informal settlements and represent, nowadays, a huge architectural and cultural heritage of the country. Due the brittle behaviour and low ductility of the building material, characterized by both low tensile and bending strength, earth constructions show high seismic vulnerability; nevertheless, though Colombian earthquake hazard level is considered very high, current national seismic building regulations do not include any reference to earthen architecture. Seismic failure mechanisms most frequently occurring to masonry architecture, as adobe buildings rehabilitation techniques and seismic behaviour improvement practices, have been widely published. This paper aims to investigate possible causes associated to failure mechanisms due to common adobe building practices in Colombia and intervention strategies, to be eventually implemented in order to reduce risks. The paper focuses on strategies and technologies for seismic retrofitting, while evaluating their effectiveness and feasibility through 'sustainability' indicators, based on literature quantitative and qualitative data, and strictly related to rural Colombian economic, social and environmental conditions, where available resources are scarce and labour often not qualified

Estudo da herança da resistência a brusone em duas cultivares de arroz (Oryza sativa).

O objetivo do presente trabalho foi de identificar o número de alelos envolvidos na expressão da resistência qualitativa à brusone nas folhas nas cultivares Cica-8 e Metica-1.Conpeex 2010

Transition metal oxides using quantum Monte Carlo

The transition metal-oxygen bond appears prominently throughout chemistry and solid-state physics. Many materials, from biomolecules to ferroelectrics to the components of supernova remnants contain this bond in some form. Many of these materials' properties strongly depend on fine details of the TM-O bond and intricate correlation effects, which make accurate calculations of their properties very challenging. We present quantum Monte Carlo, an explicitly correlated class of methods, to improve the accuracy of electronic structure calculations over more traditional methods like density functional theory. We find that unlike s-p type bonding, the amount of hybridization of the d-p bond in TM-O materials is strongly dependant on electronic correlation.Comment: 20 pages, 4 figures, to appear as a topical review in J. Physics: Condensed Matte