Chiral Zeromodes on Vortex-type Intersecting Heterotic Five-branes

We solve the gaugino Dirac equation on a smeared intersecting five-brane solution in E_8\times E_8 heterotic string theory to search for localized chiral zeromodes on the intersection. The background is chosen to depend on the full two-dimensional overall transverse coordinates to the branes. Under some appropriate boundary conditions, we compute the complete spectrum of zeromodes to find that, among infinite towers of Fourier modes, there exist only three localized normalizable zeromodes, one of which has opposite chirality to the other two. This agrees with the result previously obtained in the domain-wall type solution, supporting the claim that there exists one net chiral zeromode localized on the heterotic five-brane system.Comment: 10 pages, 2 figure

Exact solutions for supersymmetric stationary black hole composites

Four dimensional N=2 supergravity has regular, stationary, asymptotically flat BPS solutions with intrinsic angular momentum, describing bound states of separate extremal black holes with mutually nonlocal charges. Though the existence and some properties of these solutions were established some time ago, fully explicit analytic solutions were lacking thus far. In this note, we fill this gap. We show in general that explicit solutions can be constructed whenever an explicit formula is known in the theory at hand for the Bekenstein-Hawking entropy of a single black hole as a function of its charges, and illustrate this with some simple examples. We also give an example of moduli-dependent black hole entropy.Comment: 13 pages, 1 figur

Phenotypic and genotypic characterization of endophytic bacteria associated with transgenic and non-transgenic soybean plants.

Endophytic bacteria isolated from non-transgenic and transgenic Roundup Ready® glyphosate-resistant (GR) soybean plants were investigated to analyze the correspondence between phenotypic and genotypic characteristics and to determine whether or not the strains could be grouped based on the source of isolation in transgenic or non-transgenic plants, respectively. Most of the strains recovered from GR plants have shown the ability for plant growth promotion (PGP) by means of IAA production and inorganic phosphate solubilization, and 100% of the strains showed great motility (swarm or swim); in addition, 90% of the strains were able to metabolize the majority of carbon sources tested. GR soybean felds showed higher endophytes abundance than non-transgenic; however, analyzing the phylogenetic trees constructed using the partial 16SrRNA gene sequences, higher diversity was observed in non-transgenic soybean felds. Overall the majority of isolated endophytes could utilize multiple patterns of carbon sources and express resistance to antibiotics, while isolates varied widely in the PGP ability. The greater pattern and frequency of utilization of carbon sources and frequency and intensity of antibiotic resistance compared with PGP ability within the soybean endophytes community suggest that carbon sources metabolism and antibiotic resistance confer a greater relative ftness beneft than PGP ability. In conclusion, cluster analysis of the phenotypes and 16SrRNA gene sequences reveals lack of correspondence between the pattern of bacterial isolates and the transgenic character of plants, and the heterogeneity of clustering suggested that various adaptive processes, such as stress response, could have contributed to generate phenotypic variability to enhance endophytes overall ftness. Keywords Transgenic soybean · Endophytic bacteria · 16SrRNA · Antibiotics · Carbon sources metabolism · Plant growth promotio

Non-Kaehler attracting manifolds

We observe that the new attractor mechanism describing IIB flux vacua for Calabi-Yau compactifications has a possible extension to the landscape of non-Kaehler vacua that emerge in heterotic compactifications with fluxes. We focus on the effective theories coming from compactifications on generalized half-flat manifolds, showing that the Minkowski "attractor points'' for 3-form fluxes are special-hermitian manifolds.Comment: 18 pages. v2: Minor polishing, reference added. v3: More cleanup, final version for JHE

Altered proteolytic and amydolytic activity in insecticide-susceptible and -resistant strains of the maize weevil, Sitophilus zeamais

Fitness cost is usually associated with insecticide resistance and may be mitigated by increased energy accumulation and mobilization. Preliminarily evidence from tests with Sitophilus zeamais Motschulsky, the maize weevil (Coleoptera: Curculionidae) suggested possible involvement of proteinases and amylases in such a phenomenon. Therefore, trypsin-like serine-proteinases, cysteine-proteinases and α-amylases were purified and characterized from an insecticide-susceptible and two insecticide-resistant strains (one with associated fitness cost [resistant cost strain], and the other without it [resistant no-cost strain]). Trypsin-like serine-proteinases were purified by aprotinin-agarose affinity chromatography, while cysteine-proteinases were purified using thiol-sepharose affinity chromatography, and the main α-amylase of each strain was purified by glycogen precipitation and ion-exchange chromatography. The activity and inhibition profile differed among strains for each group of purified enzyme. The higher levels of activity observed for trypsin-like proteinases and amylase in the resistant no-cost strain, as well as their susceptibility to inhibition provide support for the hypothesis that enhanced trypsin-like protease and α-amylase activity may be playing a major role in mitigating fitness costs associated with insecticide resistance. In contrast, enhanced cysteine-proteinase activity is likely to play only a secondary role, if any, in mitigating the costs usually associated with insecticide resistance. Keywords: Fitness cost mitigation, Insecticide resistance, Digestive enzymes, Amylases, Proteinases

5D Attractors with Higher Derivatives

We analyze higher derivative corrections to attractor geometries in five dimensions. We find corrected AdS_3xS^2 geometries by solving the equations of motion coming from a recently constructed four-derivative supergravity action in five dimensions. The result allows us to explicitly verify a previous anomaly based derivation of the AdS_3 central charges of this theory. Also, by dimensional reduction we compare our results with those of the 4D higher derivative attractor, and find complete agreement.Comment: 18 pages, harvma

Dilaton Domain Walls and Dynamical Systems

Domain wall solutions of $d$-dimensional gravity coupled to a dilaton field $\sigma$ with an exponential potential $\Lambda e^{-\lambda\sigma}$ are shown to be governed by an autonomous dynamical system, with a transcritical bifurcation as a function of the parameter $\lambda$ when $\Lambda<0$. All phase-plane trajectories are found exactly for $\lambda=0$, including separatrices corresponding to walls that interpolate between $adS_d$ and adS_{d-1} \times\bR, and the exact solution is found for $d=3$. Janus-type solutions are interpreted as marginal bound states of these ``separatrix walls''. All flat domain wall solutions, which are given exactly for any $\lambda$, are shown to be supersymmetric for some superpotential $W$, determined by the solution.Comment: 30 pp, 11 figs, significant revision of original. Minor additional corrections in version to appear in journa

Moduli Stabilisation in Heterotic Models with Standard Embedding

In this note we analyse the issue of moduli stabilisation in 4d models obtained from heterotic string compactifications on manifolds with SU(3) structure with standard embedding. In order to deal with tractable models we first integrate out the massive fields. We argue that one can not only integrate out the moduli fields, but along the way one has to truncate also the corresponding matter fields. We show that the effective models obtained in this way do not have satisfactory solutions. We also look for stabilised vacua which take into account the presence of the matter fields. We argue that this also fails due to a no-go theorem for Minkowski vacua in the moduli sector which we prove in the end. The main ingredient for this no-go theorem is the constraint on the fluxes which comes from the Bianchi identity.Comment: 20 pages, LaTeX; references adde

O uso de valores moleculares de características produtivas e reprodutivas para seleção de touros da raça Nelore por meio de análises multivariadas.

O uso de análises multivariadas para conhecer melhor a relação entre os valores genômicos e, com isso, agrupar e selecionar os melhores animais.Pôster - graduação

Violation of the Cauchy-Schwarz inequality with matter waves

The Cauchy-Schwarz (CS) inequality -- one of the most widely used and important inequalities in mathematics -- can be formulated as an upper bound to the strength of correlations between classically fluctuating quantities. Quantum mechanical correlations can, however, exceed classical bounds.Here we realize four-wave mixing of atomic matter waves using colliding Bose-Einstein condensates, and demonstrate the violation of a multimode CS inequality for atom number correlations in opposite zones of the collision halo. The correlated atoms have large spatial separations and therefore open new opportunities for extending fundamental quantum-nonlocality tests to ensembles of massive particles.Comment: Final published version (with minor changes). 5 pages, 3 figures, plus Supplementary Materia