Prospects for Measuring Vtb via s-channel Single Top at ATLAS

The production of single top quarks via the electroweak interaction promises to provide new opportunities to both test the Standard Model and search for new physics. In particular, electroweak top production provides the only means to directly measure the CKM matrix element Vtb at ATLAS. The s-channel has the lowest rate, but is the best theoretically understood mechanism of electroweak top production. An evaluation of the potential for background suppression and Vtb measurement in this channel is presented. It is found that significant background suppression can be achieved and Vtb can be measured in the s-channel to a statistical precision of 2.8% after 30 inverse femtobarns of integrated luminosity at the LHC

Class II Phosphoinositide 3-Kinases Contribute to Endothelial Cells Morphogenesis

PMCID: PMC3539993This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

INTEGRAL timing and localization performance

In this letter we report on the accuracy of the attitude, misalignment, orbit and time correlation which are used to perform scientific analyses of the INTEGRAL data. The boresight attitude during science pointings has an accuracy of 3 arcsec. At the center of the field, the misalignments have been calibrated leading to a location accuracy of 4 to 40 arcsec for the different instruments. The spacecraft position is known within 10 meters. The relative timing between instruments could be reconstructed within 10 microsec and the absolute timing within 40 microsec.Comment: 5 pages, 2 figures, accepted for publication in A+A letters, INTEGRAL special issu

Reputation, Game Theory and Entrepreneurial Sustainability

Abstract: This manuscript provides a novel approach to reputational management as a driver of entrepreneurial sustainability, using game theory to integrate three dimensions of reputation. First, if the entrepreneur perceives reputation as a risk source, the analysis is framed as a prisoner’s dilemma schema that is solved by protecting against reputational threats from entrepreneurial sustainability. Second, if the entrepreneur perceives reputation as a competitive advantage, the analysis is framed as an innovator’s dilemma that is solved by getting reputational opportunities from entrepreneurial sustainability. Third, if reputation is perceived as a strategic asset, the analysis is framed as a coordination game schema that results in the development of a reputational intelligence skill that has the potential to become crucial for success in entrepreneurial sustainability. Consequently, this manuscript provides an original multidisciplinary analysis of reputational management by relating well-known theoretical results from game theory to organizational realities

An efficient hardware architecture for a neural network activation function generator

This paper proposes an efficient hardware architecture for a function generator suitable for an artificial neural network (ANN). A spline-based approximation function is designed that provides a good trade-off between accuracy and silicon area, whilst also being inherently scalable and adaptable for numerous activation functions. This has been achieved by using a minimax polynomial and through optimal placement of the approximating polynomials based on the results of a genetic algorithm. The approximation error of the proposed method compares favourably to all related research in this field. Efficient hardware multiplication circuitry is used in the implementation, which reduces the area overhead and increases the throughput

Características morfofisiológicas de culivares de capim-bufel submetidas a diferentes temperaturas do ar e concentrações de CO2.

O presente trabalho foi realizado com a finalidade de avaliar as características morfofisiológicas do capim-bufel (Cenchrus ciliaris L.) submetido a aumentos da temperatura do ar e concentrações de CO2. As cultivares avaliadas foram Biloela, Aridus e West Australian, mantidas em câmara de crescimento em três combinações de temperaturas (diurna/ noturna): 26°C/20°C; 29°C/23°C e 32°C/26°C associadas a duas concentrações de CO2; 370 ppm e 550 ppm. O delineamento experimental foi o inteiramente casualizado em arranjo fatorial 3 x 3 x 2 com três repetições por tratamento. Dentre as cultivares, a Aridus apresentou maior número de folhas vivas (NFV/perfilho), enquanto a West Australian teve menor comprimento de lâminas expandidas (CLEx). O aumento da temperatura diminuiu o NFV/perfilho e a duração de vida das folhas, mas aumentou o CLEx. As três cultivares responderam de maneira diferenciada ao aumento da concentração de CO2 e da temperatura, indicando que cenário climático futuro com aumento da temperatura e concentração de CO2 poderá afetar o crescimento da planta e a duração do seu ciclo de cultivo

New Halogenated Phenylbacteriochlorins and Their Efficiency in Singlet-Oxygen Sensitization

Halogenated phenylbacteriochlorins are synthesized with high yields in a two-step procedure. They have strong absorbances in the red and are very stable to air and light at room temperature. Flash photolysis measurements show that the triplet states of these bacteriochlorins have 30 μs lifetimes in deaerated toluene, that are quenched with diffusion-controlled rate constants by molecular oxygen. Time-resolved photoacoustic measurements, with nanosecond and nanocalorie resolution, show that these bacteriochlorins sensitize the formation of singlet oxygen with nearly unity quantum yield. However, singlet-oxygen phosphorescence measurements indicate that physical quenching occurs before the singlet-oxygen molecules diffuse into solution, and nearly half of the sensitized singlet states are lost

The Minimal Supersymmetric Standard Model: Group Summary Report

CONTENTS: 1. Synopsis, 2. The MSSM Spectrum, 3. The Physical Parameters, 4. Higgs Boson Production and Decays, 5. SUSY Particle Production and Decays, 6. Experimental Bounds on SUSY Particle Masses, 7. References.Comment: 121 pages, latex + epsfig, graphicx, axodraw, Report of the MSSM working group for the Workshop "GDR-Supersym\'etrie",France. Rep. PM/98-4

Inclusive search for same-sign dilepton signatures in pp collisions at root s=7 TeV with the ATLAS detector

An inclusive search is presented for new physics in events with two isolated leptons (e or mu) having the same electric charge. The data are selected from events collected from p p collisions at root s = 7 TeV by the ATLAS detector and correspond to an integrated luminosity of 34 pb(-1). The spectra in dilepton invariant mass, missing transverse momentum and jet multiplicity are presented and compared to Standard Model predictions. In this event sample, no evidence is found for contributions beyond those of the Standard Model. Limits are set on the cross-section in a fiducial region for new sources of same-sign high-mass dilepton events in the ee, e mu and mu mu channels. Four models predicting same-sign dilepton signals are constrained: two descriptions of Majorana neutrinos, a cascade topology similar to supersymmetry or universal extra dimensions, and fourth generation d-type quarks. Assuming a new physics scale of 1 TeV, Majorana neutrinos produced by an effective operator V with masses below 460 GeV are excluded at 95% confidence level. A lower limit of 290 GeV is set at 95% confidence level on the mass of fourth generation d-type quarks