Bottom production in Photon and Pomeron -- induced interactions at the LHC

In this paper we present a detailed comparison of the bottom production in gluon -- gluon, photon -- gluon, photon -- photon, pomeron -- gluon, pomeron -- pomeron and pomeron -- photon interactions at the LHC. The transverse momentum, pseudo -- rapidity and $\xi$ dependencies of the cross sections are calculated at LHC energy using the Forward Physics Monte Carlo (FPMC), which allows to obtain realistic predictions for the bottom production with one or two leading intact protons. Moreover, predictions for the the kinematical range probed by the LHCb Collaboration are also presented. Our results indicate that the analysis of the single diffractive events is feasible using the Run I LHCb data.Comment: 8 pages, 3 figures, 1 table. Version published in Physical Review

Photon and Pomeron -- induced production of Dijets in pppp, pApA and AAAA collisions

In this paper we present a detailed comparison of the dijet production by photon -- photon, photon -- pomeron and pomeron -- pomeron interactions in $pp$, $pA$ and ${\rm AA}$ collisions at the LHC energy. The transverse momentum, pseudo -- rapidity and angular dependencies of the cross sections are calculated at LHC energy using the Forward Physics Monte Carlo (FPMC), which allows to obtain realistic predictions for the dijet production with two leading intact hadrons. We obtain that \gamma \pom channel is dominant at forward rapidities in $pp$ collisions and in the full kinematical range in the nuclear collisions of heavy nuclei. Our results indicate that the analysis of dijet production at the LHC can be useful to test the Resolved Pomeron model as well as to constrain the magnitude of the absorption effects.Comment: 11 pages, 6 figures, 1 table. Improved and enlarged version published in European Physical Journal

A power management strategy for a stand-alone photovoltaic/fuel cell energy system for a 1kW application

In this paper a power management strategy is presented for a stand-alone photovoltaic (PV)/fuel cell (FC) energy system. PV is the primary power source of the system and an FC-electrolyzer combination is used as a backup and a long-term storage system. The energy in the hybrid system is balanced by the common dc bus voltage regulation. A simple hysteresis voltage control is used for dc bus voltage regulation. In this way, the fuel cell and the electrolyzer can be protected from unnecessary utilization or irregular operation (reduction of frequent start-ups and shutdowns). Simulation results obtained using Matlab and Simulink are presented to verify the effectiveness of the proposed control algorithm

Performance of a solar-hydrogen stand-alone system for residential applications

Hydrogen, as an energy storage medium, is considered a promising solution to overcome the limitation of intermittent renewable energy sources. In this paper, a residential scale solar-hydrogen based stand-alone energy system is designed, modelled and the simulated system performance under real end-use load, representative of standard European domestic electrical energy consumption, and meteorological conditions is analyzed. The sun is the primary energy source of the system and a fuel cell-electrolyzer combination is used as a backup and a long-term storage system. A battery bank is also used as energy buffer and for short time storage. Matlab/Simulink® is used for the overall system modelling and simulation. The results show that the designed solar-hydrogen system is in principle capable of operating autonomously and in a sustainable manner. The designed system is able to convert 7.6% of the total energy irradiated in one year

Squeezing generation and revivals in a cavity-ion system in contact with a reservoir

We consider a system consisting of a single two-level ion in a harmonic trap, which is localized inside a non-ideal optical cavity at zero temperature and subjected to the action of two external lasers. We are able to obtain an analytical solution for the total density operator of the system and show that squeezing in the motion of the ion and in the cavity field is generated. We also show that complete revivals of the states of the motion of the ion and of the cavity field occur periodically.Comment: 9 pages, 3 figure

Desenvolvimento e validação de chip de DNA para genotipagem em escala de acessos do programa de conservação de germoplasma e de melhoramento genético de arroz.

Neste trabalho, dados de sequenciamento, montagem e alinhamento de genomas de oito variedades de arroz foram empregados na descoberta e seleção de milhares de sítios SNP. As informações em torno das sequências que flanqueiam os SNPs selecionados foram utilizadas para desenvolver um chip de DNA para uso em genotipagem em escala. Este chip foi avaliado e validado para a genotipagem de amostras do germoplasma de arroz

Efeito de genótipo e ambiente sobre o percentual de grãos esverdeados de soja, em seis locais da região Sul de Mato Grosso do Sul, safra 2004/05.

Em grãos de soja, tem-se constatado diferentes níveis de esverdeamento entre cultivares e locais de semeadura da cultura. Com o objetivo de verificar os efeitos de genótipo e ambiente sobre a incidência de grãos esverdeados, foi conduzido o presente trabalho utilizando-se oito cultivares de soja (BRS 133, BRS 181, BRS 239, EMBRAPA 48, BRS 206, BRS 240, BRS 241 e CD 202) em seis ambientes de Mato Grosso do Sul, na safra 2004/2005bitstream/item/38718/1/BP200530.pdfDocumento on-line

Extracting samples of high diversity from thematic collections of large gene banks using a genetic-distance based approach.

Background Breeding programs are usually reluctant to evaluate and use germplasm accessions other than the elite materials belonging to their advanced populations. The concept of core collections has been proposed to facilitate the access of potential users to samples of small sizes, representative of the genetic variability contained within the gene pool of a specific crop. The eventual large size of a core collection perpetuates the problem it was originally proposed to solve. The present study suggests that, in addition to the classic core collection concept, thematic core collections should be also developed for a specific crop, composed of a limited number of accessions, with a manageable size. Results The thematic core collection obtained meets the minimum requirements for a core sample - maintenance of at least 80% of the allelic richness of the thematic collection, with, approximately, 15% of its size. The method was compared with other methodologies based on the M strategy, and also with a core collection generated by random sampling. Higher proportions of retained alleles (in a core collection of equal size) or similar proportions of retained alleles (in a core collection of smaller size) were detected in the two methods based on the M strategy compared to the proposed methodology. Core sub-collections constructed by different methods were compared regarding the increase or maintenance of phenotypic diversity. No change on phenotypic diversity was detected by measuring the trait "Weight of 100 Seeds", for the tested sampling methods. Effects on linkage disequilibrium between unlinked microsatellite loci, due to sampling, are discussed. Conclusions Building of a thematic core collection was here defined by prior selection of accessions which are diverse for the trait of interest, and then by pairwise genetic distances, estimated by DNA polymorphism analysis at molecular marker loci. The resulting thematic core collection potentially reflects the maximum allele richness with the smallest sample size from a larger thematic collection. As an example, we used the development of a thematic core collection for drought tolerance in rice. It is expected that such thematic collections increase the use of germplasm by breeding programs and facilitate the study of the traits under consideration. The definition of a core collection to study drought resistance is a valuable contribution towards the understanding of the genetic control and the physiological mechanisms involved in water use efficiency in plants

Synthesis of new azole phosphonate precursors for fuel cells proton exchange membranes

Herein we present the synthesis and characterization of new phosphonate-, bisphosphonate- and hydroxybisphosphonatebenzimidazole derivatives substituted at the N-1 position and new regioisomers phosphonate-, bisphosphonate-, and hydroxybisphosphonatebenzotriazole derivatives substituted at N-1 or N-2 positions. The compounds were characterized by NMR and IR spectroscopies, and mass spectrometry (low and high resolution) allowing the assignment of their structure, including the identification of regioisomers. These new azole monomers will be precursors for a mesoporous silica host to produce novel membrane materials with high proton conductivity for intermediate temperature proton exchange membrane fuel cells

Searching for axionlike particles with low masses in pPbpPb and PbPbPbPb collisions

The production of axionlike particles (ALPs) with small masses in ultraperipheral $Pb - p$ and $Pb - Pb$ collisions at the LHC is investigated. The cross section and kinematical distributions associated to the diphoton final state produced in the $\gamma \gamma \rightarrow a \rightarrow \gamma \gamma$ subprocesses are estimated considering a realistic set of kinematical cuts. A detailed analysis of the backgrounds is performed and the expected sensitivity to the ALP production is derived. Our results demonstrate that a future experimental analysis of the exclusive diphoton production for the forward rapidities probed by the LHCb detector can improve the existing exclusion limits on the ALP - photon coupling in the mass range 2 GeV $\le m_a \le$ 5 GeV.Comment: 6 pages, 3 figures, 2 table